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The purpose of this paper was to determine the influence of a number of measured points on results of measurements of turbine blades, which are the parts of aircraft engines. The selection of a number of points is the part of a measurement strategy in the coordinate measuring technique and determines the accuracy of measurements.

Numerical and experimental investigations were conducted. The measurements were simulated using different numbers of measured points. The simulated measurements were performed for the selected dispersion of measured points. The dispersion reflected the inaccuracy of a manufacturing process of the considered product and the uncertainty of measurements of curvilinear surfaces. To verify the accuracy of the numerical studies, experimental research was conducted. The real measurements were conducted using the selected coordinate measuring machine.

The gained results following the simulations can be very useful when selecting the appropriate number of measured points. The chosen number of points may be used during real measurements of turbine blades conducted on coordinate measuring machines. The results of numerical research indicate that there should be used the average radii of leading and trailing edges to increase the accuracy of measurements. The results of real coordinate measurements confirmed the results of simulation studies.

The main novelty of the paper is the presented methodology for determining the influence of measured points on results of measurements. The presented methodology helps the user of a coordinate measuring system select the appropriate measurement strategy of free-form surfaces applied in the aerospace industry.

The purpose of this study is to investigate the possibility of soft science measurement of motivation under strict hard science criteria from observations of individual animals and to suggest the conditions under which an observation can be classified as a measurement.

The methodology starts from reconciling second-order cybernetics/radical constructivism (SOC/RC) understanding of the central role of the observer with physical measurements, which accepts the existence of a mind-independent reality. As a result of the reconciliation, parallels were identified between the SOC/RC experiences of as_is and as_if, on the one hand, and the measurement concepts of accuracy and resolution, on the other hand. The scales of physical measurement are defined by criteria of varying strictness, and the scales that meet the strict criterion of concatenation are generally considered hard science and lead to well-defined accuracy and precision. The similarity between SOC/RC and physical measurement suggests that if accuracy and precision can be computed from observations, then the observations can be classified as measurements in a strict hard science fashion; otherwise, the observations are just observations.

A nonlinear dynamic model of motivation is reintroduced as an example for reference in measurements of motivation. If there was an agreement on its use among observers (Ethologists), which in reality is not the case, then empirical data may be collected, and the averages and spreads of parameter estimations will define a reference for an animal species. Later, observers with their own data will calibrate with the reference model, so that new observers will have calculated values of accuracy and precision for their data.

Unlike hard science whose scales of measurement are practically unambiguous, measuring the purpose of behaviour of an animal has inherent ambiguity according to the reintroduced model. The ambiguity cannot be resolved from instantaneous readings. The necessary existence of ambiguity renders the criticism of hard science invalid, that of expecting to measure motivation with a static scale as if it were temperature.

Human observers can be treated as measuring devices of motivation from observing behaviour. Each observer can have characteristic accuracy/precision, or validity/reliability, calculated from empirical data.

This is an inductive, rather than deductive, study of individual animal behaviour; the author believes it is extensible to individual human behaviour and personality studies. However, group behaviour studies are beyond its scope.

The author believes that the suggestion of ambiguity of scales of animal motivation is original, and the suggested link between SOC/RC and a mainstream hard science is new.

When building parts in a stereolithography apparatus (SLA), the user is faced with many decisions regarding how the part will be built. The quality of the build can be controlled by the user by changing one of several build style variables, including part orientation, cross sectional layer thickness, and laser hatch density. A user will probably have preferences for the part build (i.e. accuracy or speed), but may not understand how to vary the build style variables to produce the desired results. A method based on response surface methodology and multiobjective decision support is described in this paper for relating build goals to the build style variables to provide support for making build style decisions. The method is applied to the build style of a circuit breaker handle. Results indicate the method’s usefulness in supporting build style decisions. Expected behaviors of the goals with respect to the variables were confirmed and quantified. Additionally, response surface methodology was shown to be accurate and effective in modeling the relationships among variables and goals.

THE first indication that Wavis Engineering Development Co Ltd had weathered the recession and was pulling out, came in 1984 with a slight upsurge of orders. Wavis decided to be bold and to obtain sole distributorship of the Sakazaki range of multi‐spindle machining centres and also to launch their own versatile CNC Turret Machine Cell.

For the electromagnetic simulation of electrical machines, models with different ranges of values, levels of detail and accuracies are used. In this paper, numerical and two analytical models of an induction machine (IM) are analysed with respect to these aspects. The purpose of the paper is to use these analyses to discuss the suitability of the models for the simulation of various physical quantities of an IM.

An exemplary IM is simulated using the two-dimensional numerical finite element method, an analytical harmonic wave model (HWM) and an extended HWM. The simulation results are analyzed among themselves in terms of their level of detail and accuracy. Furthermore, the results of operating map simulations are compared with measured operating maps of the exemplary machine, and the accuracy of the simulation approaches is discussed in the context of measurement deviations and uncertainties.

The difference in the accuracy of the machine models depends on the physical quantity of interest. Therefore, the choice of the simulation method depends on the nature of the problem and the expected range of results. For modeling global machine quantities, such as mean torque or losses, analytical methods such as the HWM s are sufficient in many applications because the simulation results are within the range of measurement accuracy of current measurement systems. Analytical methods are also suitable for local flux density curves under certain conditions. However, for the simulation of the influence of local physical effects on the machine behavior and of temporally highly resolved quantities in saturated operating points, the accuracy of the analytical models decreases and the use of the finite element method becomes necessary.

In this paper, an extension of the HWM is used to calculate the IM, which, in contrast to the HWM, models the saturation. Furthermore, the simulation results of the different electromagnetic IM models are put into the context of the uncertainty of a measurement of several identical IMs.

The purpose of this paper is to describe the use of a test artifact proposed by NIST to quantify the dimensional accuracy of a metal additive manufacturing process. Insights from this paper are given concerning both the performance of the machine, a concept laser Mlab cusing machine, and the applicability of the NIST test artifact in characterizing accuracy. Recommendations are given for improving the artifact and standardizing a process for evaluating dimensional accuracy across the additive manufacturing industry.

Three builds of the NIST additive manufacturing test artifact were fabricated in 316 stainless steel on a concept laser Mlab cusing machine. The paper follows the procedure described by NIST for characterizing dimensional accuracy of the additive process. Features including pins, holes and staircase flats of various sizes were measured using an optical measurement system, a touch probe and a profilometer.

This paper describes the accuracy of printed features’ size and position on the test artifact, as well as surface finish on flat and inclined surfaces. Trends in variation of these dimensions are identified, along with possible root causes and remedies. This paper also describes several strengths and weaknesses in the design of the test artifact and the proposed measurement strategy, with recommendations on how to improve and standardize the process.

This paper reviews a previously proposed design and process for measuring the capabilities of additive manufacturing processes. It also suggests improvements that can be incorporated into future designs and standardized across the industry.