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This paper presents a design verification for a small Stand-Alone Photovoltaic (SAPV) system under Malaysian tropical climate. The two design methods applied in this study were Mathematical Sizing (MS) model, which claimed to be one of the best sizing methods under Malaysian tropical climate and PVSYST commercial software. The comparison on the design results demonstrated that MS and PVSYST sizing methods have similarities but also differences. The study verified that both methods showed that increasing the system voltage, will reduce the required battery capacity. Significantly, the PVSYST software was found to oversize the battery bank and PV modules capacity required to meet the total energy required from load profile assessment. The differences encountered between the MS and PVSYST software were conceivably due to the different design parameters setting namely the minimum PV module temperature threshold, ambient temperature and battery parameters involved in the design calculation. This study has highlighted several technical understandings on designing SAPV system in both design methods, that can facilitate the PV system designers to evaluate the assumptions and mathematical models applied specifically in each sizing models. [ABSTRACT FROM AUTHOR]

This paper presents the study on deformability analysis of sheet metal forming by using finite element methods (FEM). The paper particularly focuses on application of dynamic explicit and static implicit approaches to simulate metal forming of rectangular cups where different material models and contact conditions with friction are involved. Comparative studies of the results on formability of the forming process using the two approaches are presented. The simulated results are verified using results from experimental study of the deformation on the same material. Further, a comparison between a quadratic Hill anisotropic yield criterion and von Mises yield criterion with isotropic hardening has been presented. The results confirm that the dynamic explicit procedure is more efficient in simulating sheet metal forming processes. The study shows also that the finite element analysis undoubtedly gives good approximate numerical results to real processes when the material and friction anisotropy are considered. [ABSTRACT FROM AUTHOR]

In this paper, we concern at situations where we have to compare selected parameters from particular nonlinear models. A motivational examples of previously modelled data are given at the beginning. When comparing parameters from two models, it is possible to combine them into one model. But for three and more models, it is necessary to correct significance level at advance. Two approaches to solving this problem are stated, so-called Šidák correction and Bonferroni method. Results of these methods as well as results coming from the situation where significance level correction is omitted are compared based on simulated data. [ABSTRACT FROM AUTHOR]

The numerical simulation of Localised-Incremental Forging (LIF) is a challenging task. The analysis of LIF operations is often difficult, especially when several strokes are necessary to obtain the final shape of the part. The use of FE models is mandatory because incremental operations throughout a workpiece are difficult to analyse with conventional analytical methods. It is known that, in general, implicit FE models give more robust results than explicit FE models; however, with the former methodology there are several problems that must be faced. With the main goal to extend the analysis capability of LIF operations, some explicit FE models are developed in this paper and results are compared to those obtained by implicit methodology. It can be concluded that taking into account these guidelines, the developed models could be further used in the analysis of multi-strokes LIF operations, where more complicated trajectories will be required. [ABSTRACT FROM AUTHOR]