Development of an Autogyro Rotor Model with Rotorcraft's ‘Multiblade’ Simulation Approach

The University of Glasgow has involved in the research study of autogyro’s flight mechanics for more than 15 years. This paper is giving an overview of the mathematical model development of a light autogyro, emphasising on the rotor model that employs one of the existing helicopter modelling approaches developed at Glasgow, the ‘multiblade’ or the ‘rotor-disc’ modelling approach. The method is based on the analytical calculation approach of the rotor loads, in which the elemental load of the blade is analytically integrated over the whole span of the blade and forms an approximation of the rotor ‘disc’ loads as a whole. In this approach, the blade is considered as a simplified aerofoil with an average lift and drag coefficients, without capturing the aerodynamic details of each geometrical point of the blade. Validation of this model is done by comparing the trim simulation results against the existing trim flight test data acquired from the previous research of the same autogyro. There are good agreements between the simulation results and the flight test data for most of the flight parameters, not as precise as the other previously used ‘individual-blade’ model approach, but are acceptable due to the advantage this multiblade approach has as a trade-off between the fast computer processing time and the accuracy of predictions. This autogyro’s multiblade modelling approach is expected to be used in more autogyro applications where the advantages of this approach are required the most

Development of an Autogyro Rotor Model with Rotorcraft's ‘Multiblade’ Simulation Approach

The University of Glasgow has involved in the research study of autogyro’s flight mechanics for more than 15 years. This paper is giving an overview of the mathematical model development of a light autogyro, emphasising on the rotor model that employs one of the existing helicopter modelling approaches developed at Glasgow, the ‘multiblade’ or the ‘rotor-disc’ modelling approach. The method is based on the analytical calculation approach of the rotor loads, in which the elemental load of the blade is analytically integrated over the whole span of the blade and forms an approximation of the rotor ‘disc’ loads as a whole. In this approach, the blade is considered as a simplified aerofoil with an average lift and drag coefficients, without capturing the aerodynamic details of each geometrical point of the blade. Validation of this model is done by comparing the trim simulation results against the existing trim flight test data acquired from the previous research of the same autogyro. There are good agreements between the simulation results and the flight test data for most of the flight parameters, not as precise as the other previously used ‘individual-blade’ model approach, but are acceptable due to the advantage this multiblade approach has as a trade-off between the fast computer processing time and the accuracy of predictions. This autogyro’s multiblade modelling approach is expected to be used in more autogyro applications where the advantages of this approach are required the most

Reconfigurable multi-legs robot for pipe inspection: Design and gait movement

1132-1144This paper focuses on studies on reconfigurable multi-legs robotic system. The aim of this paper is to identify and acquire findings on how multi-legs robot can walk, climb vertical pipe and walk along the horizontal pipe after climbing. Three degrees of freedom (3DOF) multi-legs robot is designed and built to replace human involvement either at hazardous pipeline or to check on vertical and horizontal pipes. The robot system is tested to climb the vertical pipe and then move along horizontal pipe for inspection or other purposes. This can reduce the cost and percentage of human risk exposure during inspection on outer pipe. This multi-legs robot has more movement gaits compared to wheeled robot, but in terms of speed, wheeled robot possesses greater advantages. Therefore, this system design has combination of both wheel and multiple legs ensure that the to system has higher stability, more gait movement, and higher speed manoeuvrability. The gaits analysis for the system movement includes angle of the legs to move and selection of certain legs to perform a given operation, either walking, climbing or hanging. The target result is the system able to climb 500 mm height with 85 mm radius pipe. The potential applications for the system are: (i) to move along either on surface or underwater pipe and (ii) to be equipped with ultrasonic sensor to inspect the pipe.</em

Time and lexicographic preferences in the valuation of EQ-5D-Y with time trade-off methodology

In the valuation of EQ-5D-Y-3L, adult respondents are asked to complete composite time trade-off (cTTO) tasks for a 10-year-old child. Earlier work has shown that cTTO utilities elicited in such a child perspective are generally higher than when adults take their own perspective. We explore how differences in time preference in child and adult perspectives could explain this effect. Furthermore, as cTTO valuation in a child perspective involves explicit consideration of immediate death for a child, we also consider how cTTO utilities could be affected by decision-makers lexicographically avoiding death in children. We report the results of an experiment in which 219 respondents valued 5 health states in both adult and child perspectives with either a standard cTTO or a lead-time TTO only approach, in which immediate death is less focal. Time preferences were measured in both perspectives. Our results suggest that utilities were lower when lead-time TTO, rather than cTTO, was used. We find large heterogeneity in time preference in both perspectives, with predominantly negative time preference. The influence of time preferences on utilities, however, was small, and correcting for time preferences did not reduce differences between utilities elicited in both perspectives. Surprisingly, we found more evidence for differences in utilities between adult and child perspectives when lead-time TTO was used. Overall, these results suggest that time and lexicographic preferences affect time trade-off valuation in child and adult perspectives, but are not the explanation for differences between these perspectives. We discuss the implications of our findings for EQ-5D-Y-3L valuation

Examination of silver-graphite lithographically printed resistive strain sensors

This paper reports the design and manufacture of three differing types of resistive strain sensitive structures fabricated using the Conductive Lithographic Film (CLF) printing process. The structures, utilising two inks prepared with silver and graphite particulates as the conductive phase, have been analysed to determine electrical and mechanical properties with respect to strain, temperature and humidity when deposited on four alternative substrate materials (GlossArt, PolyArt, Teslin and Melinex)

Comprehensive review on controller for leader-follower robotic system

985-1007This paper presents a comprehensive review of the leader-follower robotics system. The aim of this paper is to find and elaborate on the current trends in the swarm robotic system, leader-follower, and multi-agent system. Another part of this review will focus on finding the trend of controller utilized by previous researchers in the leader-follower system. The controller that is commonly applied by the researchers is mostly adaptive and non-linear controllers. The paper also explores the subject of study or system used during the research which normally employs multi-robot, multi-agent, space flying, reconfigurable system, multi-legs system or unmanned system. Another aspect of this paper concentrates on the topology employed by the researchers when they conducted simulation or experimental studies

Instability, Intermixing and Electronic Structure at the Epitaxial LaAlO3/SrTiO3(001) Heterojunction

The question of stability against diffusional mixing at the prototypical LaAlO3/SrTiO3(001) interface is explored using a multi-faceted experimental and theoretical approach. We combine analytical methods with a range of sensitivities to elemental concentrations and spatial separations to investigate interfaces grown using on-axis pulsed laser deposition. We also employ computational modeling based on the density function theory as well as classical force fields to explore the energetic stability of a wide variety of intermixed atomic configurations relative to the idealized, atomically abrupt model. Statistical analysis of the calculated energies for the various configurations is used to elucidate the relative thermodynamic stability of intermixed and abrupt configurations. We find that on both experimental and theoretical fronts, the tendency toward intermixing is very strong. We have also measured and calculated key electronic properties such as the presence of electric fields and the value of the valence band discontinuity at the interface. We find no measurable electric field in either the LaAlO3 or SrTiO3, and that the valence band offset is near zero, partitioning the band discontinuity almost entirely to the conduction band edge. Moreover, we find that it is not possible to account for these electronic properties theoretically without including extensive intermixing in our physical model of the interface. The atomic configurations which give the greatest electrostatic stability are those that eliminate the interface dipole by intermixing, calling into question the conventional explanation for conductivity at this interface - electronic reconstruction. Rather, evidence is presented for La indiffusion and doping of the SrTiO3 below the interface as being the cause of the observed conductivity

Fermi-edge singularities in linear and non-linear ultrafast spectroscopy

We discuss Fermi-edge singularity effects on the linear and nonlinear transient response of an electron gas in a doped semiconductor. We use a bosonization scheme to describe the low energy excitations, which allows to compute the time and temperature dependence of the response functions. Coherent control of the energy absorption at resonance is analyzed in the linear regime. It is shown that a phase-shift appears in the coherent control oscillations, which is not present in the excitonic case. The nonlinear response is calculated analytically and used to predict that four wave-mixing experiments would present a Fermi-edge singularity when the exciting energy is varied. A new dephasing mechanism is predicted in doped samples that depends linearly on temperature and is produced by the low-energy bosonic excitations in the conduction band.Comment: long version; 9 pages, 4 figure

A scenario modeling pipeline for COVID-19 emergency planning

Coronavirus disease 2019 (COVID-19) has caused strain on health systems worldwide due to its high mortality rate and the large portion of cases requiring critical care and mechanical ventilation. During these uncertain times, public health decision makers, from city health departments to federal agencies, sought the use of epidemiological models for decision support in allocating resources, developing non-pharmaceutical interventions, and characterizing the dynamics of COVID-19 in their jurisdictions. In response, we developed a flexible scenario modeling pipeline that could quickly tailor models for decision makers seeking to compare projections of epidemic trajectories and healthcare impacts from multiple intervention scenarios in different locations. Here, we present the components and configurable features of the COVID Scenario Pipeline, with a vignette detailing its current use. We also present model limitations and active areas of development to meet ever-changing decision maker needs

Questions and concerns about HPV vaccine: A communication experiment

OBJECTIVES: We sought to identify effective responses to parents’ questions and concerns about human papillomavirus (HPV) vaccine. METHODS: In 2017–2018, we surveyed a national sample of 1196 US parents of children aged 9 to 17 years. We recorded brief videos of a pediatrician providing messages that addressed 7 HPV vaccination topics that commonly elicit questions or concerns (eg, recommended age). We randomly assigned parents to 1 of the message topics; parents then viewed 4 videos on that topic in random order and evaluated the messages. RESULTS: Parents were more confident in HPV vaccine when they were exposed to messages that addressed lack of knowledge about HPV vaccine (b = 0.13; P = .01), messages that included information about cancer prevention (b = 0.11; P < .001), messages that required a higher reading level (b = 0.02; P = .01), and messages that were longer (b = 0.03; P < .001). Parents were less confident in HPV vaccine when exposed to messages in which urgency was expressed (b = −0.06; P = .005). Analyses conducted by using HPV vaccine motivation as an outcome revealed the same pattern of findings. CONCLUSIONS: We provide research-tested messages that providers can use to address parents’ HPV vaccination questions and concerns about 7 common topics. Important principles for increasing message effectiveness are to include information on the benefits of vaccination (including cancer prevention) and avoid expressing urgency to vaccinate when addressing parents' questions or concerns. Additionally, providers may need to be prepared to have longer conversations with parents who express concerns about HPV vaccine, especially regarding safety and side effects