Self-Healing Control Framework Against Actuator Fault of Single-Rotor Unmanned Helicopters

Unmanned helicopters (UHs) develop quickly because of their ability to hover and low speed flight. Facing different work conditions, UHs require the ability to safely operate under both external environment constraints, such as obstacles, and their own dynamic limits, especially after faults occurrence. To guarantee the postfault UH system safety and maximum ability, a self‐healing control (SHC) framework is presented in this chapter which is composed of fault detection and diagnosis (FDD), fault‐tolerant control (FTC), trajectory (re‐)planning, and evaluation strategy. More specifically, actuator faults and saturation constraints are considered at the same time. Because of the existence of actuator constraints, usable actuator efficiency would be reduced after actuator fault occurrence. Thus, the performance of the postfault UH system should be evaluated to judge whether the original trajectory and reference is reachable, and the SHC would plan a new trajectory to guarantee the safety of the postfault system under environment constraints. At last, the effectiveness of proposed SHC framework is illustrated by numerical simulations

Plasmonic nano-resonator enhanced one-photon luminescence from single gold nanorods

Strong Stokes and anti-Stokes one-photon luminescence from single gold nanorods is measured in experiments. It is found that the intensity and polarization of the Stokes and anti-Stokes emissions are in strong correlation. Our experimental observation discovered a coherent process in light emission from single gold nanorods. We present a theoretical mode, based on the concept of cavity resonance, for consistently understanding both Stokes and anti-Stokes photoluminescence. Our theory is in good agreement of all our measurements.Comment: 14 pages, 7 figures, 2 table

Potential use of gut microbiota composition as a biomarker of heat stress in monogastric species: A review

SIMPLE SUMMARY: Heat stress is a significant environmental challenge faced by food animal production worldwide because of its adverse effects on animal performance and productivity. Trillions of microorganisms living in the gut are essential for host health by participating in various digestive, immune, and metabolic activities. At the same time, they are known to be sensitive to changes in the surrounding environment. The present review summarizes current research progress of how the gut microbial community responds to elevated ambient heat in monogastric animal species and discusses the use of the gut microbiota composition as a potential indicator for heat stress. ABSTRACT: Heat stress is a current challenge for livestock production, and its impact could dramatically increase if global temperatures continue to climb. Exposure of agricultural animals to high ambient temperatures and humidity would lead to substantial economic losses because it compromises animal performance, productivity, health, and welfare. The gut microbiota plays essential roles in nutrient absorption, energy balance, and immune defenses through profound symbiotic interactions with the host. The homeostasis of those diverse gut microorganisms is critical for the host’s overall health and welfare status and also is sensitive to environmental stressors, like heat stress, reflected in altered composition and functionality. This article aims to summarize the research progress on the interactions between heat stress and gut microbiome and discuss the potential use of the gut microbiota composition as a biomarker of heat stress in monogastric animal species. A comprehensive understanding of the gut microbiota’s role in responding to or regulating physiological activities induced by heat stress would contribute to developing mitigation strategies

Design study for healthy campus landscapes in Aotearoa New Zealand : A thesis submitted in fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University

Internationally, mental health concerns have become severe for both university students and staff. The World Health Organisation addressed the importance of maintaining campus users’ health by publishing the Okanagan Charter: An International Charter for Health Promoting University and Colleges in 2015, that recognised universities’ ability and responsibility to embed health into all aspects of universities’ everyday activities and so lead health promotion actions for the wider society. However, only minimal research has been conducted to advance the healthy university agenda in New Zealand universities. Studies have been conducted to explore ways of building a health-promoting campus, ie. a salutogenic campus, however, not much attention has given to the design of the physical environment of campuses that supports healthy behaviours and encourages healthy life choices. Therefore, the main aim of this study was to investigate and evaluate the relaxation affordances of existing campus landscapes from campus users’ perspectives and provide suggestions for the future design of healthy campuses, especially for New Zealand universities. A comparative multi-case study was conducted with 65 participants including students, staff, and medical workers on campus from the city campus of the University of Auckland in Auckland, Lincoln University in Christchurch, and University of Otago in Dunedin, in terms of their relaxation experience on campus during working hours. In-depth individual interviews were done during semester time in September and October 2018 with participants using a mental mapping exercise and an optional walking interview if the participants had the time. This study showed the health and well-being significance and potential of campus landscapes. Interviews with participants across the three campuses revealed use patterns of campus landscapes for relaxation and the design characteristics of identified relaxation spaces on campuses. Natural landscapes were found to be significant for positive relaxation experience, which further signified the health and well-being value of biophilic design. Proximity to greenery and biodiversity of space were identified as two indicators to measure the biophilic level of space and presumed relaxation potential of a space. The design characteristics of relaxation campus spaces found in this study were also valuable for the creation of other health-promoting everyday environments such as working environments in the city. Therefore, this study not only contributes to the healthy university agenda but also to public health promotion through a settings-based approach