Nest excavation in social insects is an integral part of a colony’s life cycle. Soil-dwelling colonies build complex systems of narrow underground chambers and tunnels spanning thousands of insect body lengths below the ground. The nest excavation is performed by multiple animals simultaneously and is governed by local interactions of the workers with environment and other workers. The challeng...

This paper introduces a Cartesian impedance control framework in which reaction forces exceeding control authority directly reshape bucket motion during successive excavation passes. This novel approach to excavation results in an iterative process that does not require explicit prediction of terrain forces. This is in contrast to most excavation control approaches that are based on the generat...

The ability to accurately and consistently predict deformation of deep foundation pit in civil engineering is required by the designer and manager in planning and conducting construction activities. Since deformation of deep foundation pit that belongs to a multi-variable nonlinear system evolution with time-varying is vague and uncertain, it is prone to a certain degree of prediction errors. T...

BACKGROUND To describe the clinical and optical coherence tomography (OCT) features of focal choroidal excavation in Chinese patients. METHODS Retrospectively, thirty-seven eyes (in 31 patients) that demonstrated focal choroidal excavation on spectral-domain OCT were collected. Their clinical characteristics and other features were also collected and analyzed. RESULTS In total, 42 focal cho...

Bioretention cells are incorporated as part of low impact development LID because of their ability to release influent runoff as exfiltration to the soil or evapotranspiration to the atmosphere. However, little care is taken as to the techniques used to excavate bioretention cells, and there is little concern as to the soil-moisture condition during excavation. Certain excavation techniques and...