The New Dimension to Resolution: Can it be resolved?

In the metrology community, there is an ongoing debate over which contributors to the Unit Under Test (UUT) belong in the expanded uncertainty calculation of the measurement process used for calibration. This is also known as Calibration Process Uncertainty (CPU); CPU is the denominator when calculating a Test Uncertainty Ratio (TUR). This paper presents examples that illustrate why the best practices outlined in documents such as ILAC-P14:09/2020 and the ANSI/NCSLI Z540.3 Handbook should be followed regarding the contributors for the CPU. Instead of drafting their own test protocols and standards, calibration laboratories and manufacturers are advised to correctly calculate both uncertainty and risk. Performing these calculations is part of an ethical approach to calibration that avoids shifting more risk to the Industry and ultimately mitigates global consumer's risk. Furthermore, outdated approaches to calculations, such as Test Accuracy Ratio (TAR), must be discontinued, and efforts to change the agreed-upon definition of Test Uncertainty Ratio (TUR) should cease since modern computing can provide measurements that are more accurate and reliable.

Gaussian Process As a Benchmark for Optimal Sensor Placement Strategy

<div> <div> <div> <p>Optimal sensor placement is an important problem to look at. This problem becomes all the more relevant nowadays due to advancements in infrastructure monitoring robotic technologies including underground sensing. While there are multiple ways to solve optimal sensor placement problems, one of the most generic methods available is Bayesian Optimization and its variants. In this paper, we present a simple benchmark- like formulation for exploiting Gaussian Process uncertainty for sensor placement to measure a scalar field. </p> </div> </div> </div>

Gaussian Process As a Benchmark for Optimal Sensor Placement Strategy

<div> <div> <div> <p>Optimal sensor placement is an important problem to look at. This problem becomes all the more relevant nowadays due to advancements in infrastructure monitoring robotic technologies including underground sensing. While there are multiple ways to solve optimal sensor placement problems, one of the most generic methods available is Bayesian Optimization and its variants. In this paper, we present a simple benchmark- like formulation for exploiting Gaussian Process uncertainty for sensor placement to measure a scalar field. </p> </div> </div> </div>

Sensor-integrated tap holder for process uncertainty detection based on tool vibration and axial length compensation sensors

The tapping process is one of the most widespread manufacturing processes for internal threads, usually carried out at the end of the value chain. Any non-compliance with required quality standards or even the destruction of the thread due to process uncertainty in the tapping process is therefore subjected to high rework costs. Possible process uncertainties in the tapping process can be triggered by synchronization errors between feed rate and spindle speed, axis offset, faulty core holes and wear of the tapping tool. In order to detect process uncertainties during tapping and thus provide a basis for initiating countermeasures, a sensor-integrated tap holder was developed. This paper presents the realized concept of a rotating telemetry unit for signal processing, data acquisition and wireless data transmitting via WiFi standard on basis of low-cost embedded systems. Furthermore, two unique sensor concepts for measuring close-to-tool vibrations and the axial length compensation of the tapping tool are shown. Based on the sensor data in combination with feature engineering methods, process uncertainty during tapping are detected.

Weibull distribution of selective laser melted AlSi10Mg parts for compression testing

Selective laser melting (SLM) is an additive manufacturing process to fabricate three-dimen- sional structures by fusing powder particles using a computer-guided laser source. The SLM process can produce lightweight bespoke designs, having high strength comparable to con- ventional components. However, the developed surface texture and some of the mechanical properties are still sub-standard compared to the conventional components. The process un- certainty can produce inconsistency in parts’ properties, even those prepared concurrently, affecting SLM parts' repeatability and quality. Therefore, designing applications based on the most probable outcome of the desired properties can embrace process uncertainty. Weibull distribution is a statistical-based probability distribution method that measures the likelihood of the values’ occurrence of any random variable falling in a specific set of values. In this study, the Weibull distribution measured the relative likelihood (90% probability) of the compressive yield, and ultimate strength of the SLM prepared AlSi10Mg samples in a given 22 random sample size. The results showed that the compressive yield and ultimate strength fall between 321 MPa to 382 MPa and 665 MPa to 883 MPa.

Spatio-temporal modeling of the effect of selected environmental and land-use drivers on acid grassland vegetation

Spatial and temporal pin-point plant cover monitoring data are fitted in a structural equation model in order to understand and quantify the effect of selected environmental and land-use drivers on the observed variation and changes in the vegetation of acid grasslands. The important sources of measurement- and sampling uncertainties have been included using a hierarchical model structure. Furthermore, the measurement- and sampling uncertainties are separated from the process uncertainty, which is important when generating ecological predictions. Generally, increasing atmospheric nitrogen deposition leads to more grass-dominated acid grassland habitats at the expense of the cover of forbs. Sandy soils are relatively more acidic, and the effect of soil type on the vegetation includes both direct effects of soil type and indirect effects mediated by the effect of soil type on soil pH. Both soil type and soil pH affected the vegetation of acid grasslands. Even though only a small part of the temporal variation in cover was explained by the model, it will still be useful to quantify the uncertainties when using the model for generating local ecological predictions and adaptive management plans.

Flagella Ca2+ elevations regulate pausing of retrograde intraflagellar transport trains in adherent Chlamydomonas flagella

The movement of ciliary membrane proteins is directed by transient interactions with intraflagellar transport (IFT) trains. The green alga Chlamydomonas has adapted this process for gliding motility, using IFT to move adhesive glycoproteins (FMG-1B) in the flagella membrane. Although Ca2+ signalling contributes directly to the gliding process, uncertainty remains over the mechanisms through which Ca2+ acts to influence the movement of IFT trains. Here we show that flagella Ca2+ elevations regulate IFT primarily by initiating the movement of paused retrograde IFT trains. Flagella Ca2+ elevations exhibit complex spatial and temporal properties, including high frequency repetitive Ca2+ elevations that prevent the accumulation of paused retrograde IFT trains. We show that flagella Ca2+ elevations disrupt the IFT-dependent movement of microspheres along the flagella membrane. The results suggest that flagella Ca2+ elevations directly disrupt the interaction between retrograde IFT particles and flagella membrane glycoproteins to modulate gliding motility and the adhesion of the flagellum to a surface.

Measuring Sensors Calibration in Worm Gear Rolling Testers

The ISO standard regulating gear-rolling measurement does not specify in detail the calibration and verification procedures for this type of equipment. This may be one of the reasons for the lack of reproducibility in these rolling tests. The uncertainty budget method, which is the most appropriate way to know the accuracy of this dynamic measurement, shows that the measuring sensors’ accuracy is only a part of the total measurement process uncertainty. In this work, a new calibration and verification procedure for a worm gear rolling tester is presented, based on machine tool, coordinate measuring machine and gear measuring instruments’ calibration techniques. After compensating numerically for the measuring instruments, it has been evaluated how the error components of each movement affect the meshing point, a fundamental factor to ensure a good gear transmission. The study shows that there are unintentional position variations, not detected by the measuring sensors, that have to be identified and quantified in the calibration for their later inclusion in the uncertainty budget. In this way, the measurement uncertainty could be reduced, and thus improve the reproducibility of these testers, as a preliminary stage to the development of optimized rolling measurement equipment to solve current limitations.