The accurate measurement of position and orientation for shearers is a key technology in realizing an automated, fully-mechanized, coal mining face. Since Global Positioning System (GPS) signal cannot arrive at the coal mine underground, wireless sensor network positioning system cannot operate stably in the coal mine; thus a strap-down inertial navigation system (SINS) is used to measure the position and orientation of the shearer. Aiming at the problem of the SINS accumulative error, this paper proposes a positioning error correction method based on the motion constraint-aided SINS zero velocity updated (ZUPT) model. First of all, a stationary state detection model of the shearer is built with median filter based on the acceleration and angular rate measured by the SINS. Secondly, the motion of the shearer is analyzed using coal mining technology, then the motion constraint model of the shearer is established. In addition, the alternate action between the motion constraint model and the ZUPT model is analyzed at the process of movement and cessation of the shearer, respectively; hence, the motion constraint-aided SINS ZUPT model is built. Finally, by means of the experimental platform of the SINS for the shearer, the experimental results show that the maximum position error with the positioning model proposed in this paper is 1.6 m in 180 s, and increases by 92.0% and 88.1% compared with the single motion constraint model and single ZUPT model, respectively. It can then restrain the accumulative error of the SINS effectively.

Scholars from a variety of disciplines have been working to unravel the complexities of geodesign as an approach to tackling a host of problems. We argue that a mature understanding of geodesign requires a systemic perspective to organize the interconnections between ecological, social and economic conditions at multiple spatial and temporal scales. We reviewed definitions and perspectives of geodesign and key concepts of ecological systems thinking to develop a new framework for landscape architecture. We provide the state-of-the-art in geodesign within the context of systems thinking and coupled human-environmental resilience. We show that geodesign is capable to encourage public participation and interdisciplinary collaboration through its systemic planning processes and synergetic technologies. The thrust of geodesign-related research is the emerging paradigm of landscape-based sustainability. While landscape architecture is complex in many aspects, the integrated framework promotes our understanding about its social-ecological potential, spatial-temporal association and resilience of coupled human-environment systems. Based on the findings, we outline key contributions, implications, challenges and recommendations for future research.

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Advances in energy systems for the valorization of the aqueous byproduct generated from the hydrothermal processing of biomass: a perspective and review of the recent progress.