Development of a Novel System for Adaptive Machining of Near-Net-Shape Components

Near-net-shape components are popular among the aerospace industry for low material waste and high manufacturing efficiency. However, it is difficult to machine such components into final shapes because the machining allowance is often distributed unevenly and even insufficient. This paper proposed a novel system for adaptive machining near-net-shape components, which integrates units like on-machine measurement based on probe and ultrasonic-sensor, machining allowance constrained localization, tolerance range constrained shape reconstruction, and TCP (tool cutter position) template-based NC programming. Firstly, localization and free form deformation (FFD)-based shape construction are performed within the tolerance ranges of the component, and an even distribution of the machining allowance can be obtained. Next, the quick NC programming that directly manipulates the TCPs by using spatial deformation is introduced. Last, the data transmission between units is illustrated. A case study of the machining titanium turbine blade is performed, which validates the proposed system.

Deformation motion tracks sliding changes through summer, western Greenland

Surface speeds in Greenland's ablation zone undergo substantial variability on an annual basis which are presumed to mainly be driven by changes in sliding. Yet, meltwater-forced changes in ice–bed coupling can also produce variable deformation motion, which impacts the magnitude of sliding changes inferred from surface measurements and provides important context to flow dynamics. We examine spatiotemporal changes in deformation, sliding and surface velocities over a 2-year period using GPS and a dense network of inclinometers installed in borehole grid drilled in western Greenland's ablation zone. We find time variations in deformation motion track sliding changes through the summer and entire measurement period. A distinct spatial deformation and sliding pattern is also observed within the borehole grid which remains similar during winter and summer flow. We suggest that positively covarying sliding and deformation across seasonal timescales is characteristic of passive areas that are coupled to regions undergoing transient forcing, and the spatial patterns are consistent with variations in the local bed topography. The covarying deformation and sliding result in a 1.5–17% overestimate of sliding changes during summer compared to that inferred from surface velocity changes alone. This suggests that summer sliding increases are likely overestimated in many locations across Greenland.

Measurement of Deformation Heterogeneity during Shale Swelling using Digital Image Correlation

Rock-fluid interactions in shale formations is one of the main sources of wellbore instability issues, inadequate stimulation performance or the sealing efficiency of shales for carbon dioxide storage in subsurface formations. For better planning of these operations, it is important to understand the mechanisms behind these interactions. These issues are especially prevalent in clay-rich shales. Conventional techniques to quantify these shale-fluid interactions comprise of measuring swelling in powdered rock grains or measurement of deformation in the whole pieces of core using LVDT and strain gages. However, the contribution from individual laminae to overall deformation cannot be evaluated using these classical methods. In this study, we developed an experimental setup to evaluate the spatial deformation in shale during interaction with water using digital image correlation (DIC). Deformation of two shale samples, with 34 wt% to 51 wt% clay content, were studied. White paint was used to generate a random speckle pattern on the specimen and then immersed in deionized water. The deformation process was captured using a digital camera and images were analyzed using DIC to quantify the deformation. The implementation of the DIC technique enables the visualization and quantification of spatial deformation in the specimen during interacting with water. The results show localization of large strains in select laminations. The results provide a better understanding of shale deformation when interacting with water in comparison to traditional measurements that can provide only an average strain value.

Entanglement Robustness via Spatial Deformation of Identical Particle Wave Functions

We address the problem of entanglement protection against surrounding noise by a procedure suitably exploiting spatial indistinguishability of identical subsystems. To this purpose, we take two initially separated and entangled identical qubits interacting with two independent noisy environments. Three typical models of environments are considered: amplitude damping channel, phase damping channel and depolarizing channel. After the interaction, we deform the wave functions of the two qubits to make them spatially overlap before performing spatially localized operations and classical communication (sLOCC) and eventually computing the entanglement of the resulting state. This way, we show that spatial indistinguishability of identical qubits can be utilized within the sLOCC operational framework to partially recover the quantum correlations spoiled by the environment. A general behavior emerges: the higher the spatial indistinguishability achieved via deformation, the larger the amount of recovered entanglement.

USING THE PRINCIPLES OF AUTOMATED OPTICAL IMAGE RECOGNITION TO ASSESS THE STRUCTURAL STABILITY OF KNITTED FABRICS

The article shows the possibility of determining the characteristics of stretch deformation of knitted fabrics by optoelectronic processing of digital images using the developed software. The technique is applicable for knitted fabrics of sparse structures of any fibrous composition. The tests are carried out on a developed device that implements the possibility of spatial deformation of the samples. As a quantitative indicator of the change in the structure of the knitted fabric under tension, a coefficient, that characterises the change in the structure by increasing the through porosity of the fabric, is used. The stability of the structure of the knitted fabric is evaluated by an indicator that determines the recoverability of the loop structure after rest. The method was tested on linen knitted fabrics. The results of experimental studies should be used at the design stage of products to create knitted fabrics resistant to the action of operational loads.