Micro-scale Realization of Compliant Mechanisms: Manufacturing Processes and Constituent Materials—A Review

Compliant micromechanisms (CMMs) acquire mobility from the deflection of elastic members and have been proven to be robust by millions of silicon MEMS devices. However, the limited deflection of silicon impedes the realization of more sophisticated CMMs, which often require larger deflections. Recently, some novel manufacturing processes have...

A CNN-LSTM Method for the Morphology Evolution Prediction of Beach Mega-Nourishment

Sand nourishment is widely adopted as an effective soft approach to provide long-term coastal safety, protect the ecology environment, and promote tourism and recreation. With the increase in frequency and expenses in beach nourishment worldwide, an adequate prediction of morphology evolution is greatly desired for coastline management. Based on...

Environmental impact evaluation model of dam breach — Considering the uncertainty feature of environment

The environmental impact of dam breach has the features of complexity and uncertainty. There is a lack of systematic and comprehensive research on the environmental impact of dam breach in China. Considering such fuzziness of environment evaluation and the lack of precise data, this work chooses the method of multi-index comprehensive...

Discrete lattice fracture modelling of hydrated cement paste under uniaxial compression at micro-scale

A combination of laboratory experiments and numerical simulations at multiple length scales can provide in-depth understanding of fracture behaviour of hydrated cement paste (HCP). To that end, the current work presents a numerical study on compressive failure of hydrated cement paste (HCP) at the micro-scale. Virtual specimens consisting of...

A method for fast evaluation of potential consequences of dam breach

Dam breach has catastrophic consequences for human lives and economy. In previous studies, empirical models are often, to a limited extent, due to the inadequacy of historical dam breach events. Physical models, which focus on simulating human behavior during floods, are not suitable for fast analysis of a large number of dams due to the...

Fully controlled photonic spin in highly confined optical field

As an intrinsic attribute of light, the spin angular momentum (SAM) of photons has aroused considerable attention because of the fascinating properties emerging from light–matter interactions. We show that a diffraction-limited focal field with a steerable photonic spin structure in three dimensions can be produced under a 4π microscopic...

Improved set pair analysis and its application to environmental impact evaluation of dam break

Despite the rapid development of risk analysis in dam engineering, there is a relative absence of research on the environmental impact of dam break. As a systematic theory, set pair analysis has a good effect in dealing with uncertainties, although the result is relatively rough and easy to distort. A connection degree of five grades and a...

"on Water" Direct Organocatalytic Cyanoarylmethylation of Isatins for the Diastereoselective Synthesis of 3-Hydroxy-3-cyanomethyl Oxindoles

An "on water" organocatalytic cyanoarylmethylation of aryl acetonitrile to isatins is developed, giving products in high yields and up to excellent diastereoselectivities. A remarkable enhancement of reaction rates and diastereoselectivities by water was observed under mild conditions. Moreover, this approach provides a highly efficient and...