Two piston-cylinder assemblies with large nominal diameters of 50 mm and 35 mm, which are intended to establish new primary pressure standards, have been set up in the National Metrology Centre, Agency for Science Technology and Research, (NMC, A*Star), the national metrology institute of Singapore. These two assemblies have been calibrated by Geometry Metrology Standards for the properties of straightness, roundness, and diameters. Based on the calibrated data of properties, a known and proven least square method for three-dimensional geometry is applied to determine the effective areas at atmospheric pressure and temperature 20 o C for these two assemblies. The present study proposed improved models with higher-order polynomial equation and inclusion of frequency term. By using the present improved models, the residual uncertainty in modelling can be reduced to better fit the roundness and straightness of the cylinder. The determined effective areas from dimensional properties are compared with those by the cross float method based on proven pressure standards. The comparison results show good agreement, validating the traceability of the present data by using least square method. It is also verified that least square method is suitable to be used for the piston-cylinder assemblies with large nominal diameter to calculate the effective area accurately. In addition, cross-float of these two large piston-cylinders with the effective areas determined is applied to calculate the pressure. The deviation of the pressure does not exceed 6 × 10^-6 over the pressure range (50 to 520) kPa in gauge mode.

Due to the wind power capacity energy grow exponential, interest in operation maintenance is increasing. A proper pitch controller must be designed to extend the life cycle of some wind turbine (WT) components such as blades or tower. The pitch control system has two main, but conflicting, objectives. On the one hand, it seeks to maximize the wind energy captured and converted into electrical energy. On the other hand, it seeks to minimize fatigue and mechanical load. Various metrics are proposed to achieve a compromise solution that balances these objectives. A WT of 100 kW is used to validate pitch control strategies.

Diagnostics means instrumental measurement without dismantling. So measuring the engines on rolling roads is not incorporated in this concept, as this measurement is accomplished on engines taken out from vehicles. During service, it is often necessary to measure the performance of the engines, or to judge the performance projection of some corrections. The new method discussed in this article provides a solution to this problem.

Digital image analysing methods are widely used for evaluating local deformations in sheet metal tests and forming processes. The paper is focusing on tensile tests of uniform and non-uniform width flat specimens made of aluminum alloys, which are suitable for demonstrating Lüders strain, Portevin-Le Chatelier (PLC) effect and for determination of Forming Limit Curve. Tests were carried out using GOM-ARAMIS® digital image analysis hardware and software. Observation of local deformations during tensile tests showed that initiation and evolution of local strains depend on the position of specimens related to rolling direction of sheet. Using non-uniform width specimens the local deformations are concentrated on the smallest cross-section in the final stage of tensile test. The measured major and minor strains give points of FLC.

Pellets production and consumption are steadily increasing as a kind of energy source. The production and combustion properties of pellets are defined by molecular structure and elemental composition of raw materials. Quality control tools are different in terms of areas they cover the pellet-production cycle, but it is somewhat typical that they regulate only the origin of raw materials. In the light of these deficiencies, the evaluation of the quality properties in finished product had been overviewed. There are standardized analytical methods to the biomass product qualification, and these methods are capable to the raw material qualification too. Using these methods together with the control and diagnostics of production parameter, the finished product quality can be forecasted with high accuracy. An evaluation process is proposed in the paper for the measurement methods assessment. The introduced evaluation solution is ranking these methods, based on measuring device-needed, time-requirement and measurement complexity.