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A high-fidelity simulation platform helps to verify the feasibility of the controller and reduce the cost of subsequent experiments. Therefore, this paper aims to design a high-fidelity hardware-in-the-loop (HIL) simulation platform for the tail-sitter vehicles.

The component breakdown approach is used to develop a more reliable model. Thruster dynamics and ground contact force are also modeled. Accurate aerodynamic coefficients are obtained through wind tunnel tests. This simulation system adopts a mode transition method to achieve continuous simulation for all flight modes.

Simulation results are in good agreement with the flight log and successfully predict the state of the vehicle.

First, the effects of the propeller slipstream are considered. Second, most researchers ignore the parasitic drag caused by the landing gear and other appendages, which is discussed in this study. Third, a ground contact model is implemented to allow a realistic simulation of the takeoff and landing phases. Fourth, complete wind tunnel tests are conducted to obtain more accurate aerodynamic coefficients. Finally, a mode transition method is deployed in the HIL simulation system to achieve continuous simulation for all flight modes.

The purpose of this paper is to present the development of hardware‐in‐the‐loop simulation (HILS) for visual target tracking of an octorotor unmanned aerial vehicle (UAV) with onboard computer vision.

HILS for visual target tracking of an octorotor UAV is developed by integrating real embedded computer vision hardware and camera to software simulation of the UAV dynamics, flight control and navigation systems run on Simulink. Visualization of the visual target tracking is developed using FlightGear. The computer vision system is used to recognize and track a moving target using feature correlation between captured scene images and object images stored in the database. Features of the captured images are extracted using speed‐up robust feature (SURF) algorithm, and subsequently matched with features extracted from object image using fast library for approximate nearest neighbor (FLANN) algorithm. Kalman filter is applied to predict the position of the moving target on image plane. The integrated HILS environment is developed to allow real‐time testing and evaluation of onboard embedded computer vision for UAV's visual target tracking.

Utilization of HILS is found to be useful in evaluating functionality and performance of the real machine vision software and hardware prior to its operation in a flight test. Integrating computer vision with UAV enables the construction of an unmanned system with the capability of tracking a moving object.

HILS for visual target tracking of UAV described in this paper could be applied in practice to minimize trial and error in various parameters tuning of the machine vision algorithm as well as of the autopilot and navigation system. It also could reduce development costs, in addition to reducing the risk of crashing the UAV in a flight test.

A HILS integrated environment for octorotor UAV's visual target tracking for real‐time testing and evaluation of onboard computer vision is proposed. Another contribution involves implementation of SURF, FLANN, and Kalman filter algorithms on an onboard embedded PC and its integration with navigation and flight control systems which enables the UAV to track a moving object.

The purpose of this study is to examine the influence of an urban folktale on the purchasing intentions and buying behaviour of the consumer. Specifically, it examines a rumour involving fashion designer Tommy Hilfiger, in which he purportedly made disparaging statements about African‐Americans. A survey of African‐American generation Xers revealed a relationship between the rumour and the decision to purchase Tommy Hilfiger clothing. Implications of the findings are discussed.

Marketing management, Sports marketing.

The case is targeted at students of postgraduate and undergraduate programmes in business administration, specialising in marketing management/sports marketing.

The Hockey India League (HIL) failed to make its mark. After the grand success of the Indian Premier League in India, there were hopes afloat for the HIL to follow suit. However, while the Pro Kabaddi League and the Premier Badminton League received much appreciation from a devout audience, the HIL did not quite live up to its expectations. With its evident failure for two consecutive seasons, investor sentiments were at an all-time low and most stakeholders wanted to back out. The future of the HIL now hangs in the balance, with the uncertainty of whether it should be shut down or given one more chance.

The participants are required to understand the Indian sports environment and the factors that play a major role in making a sport not only popular but also lucrative from the point of view of the investors. They will be called upon to improvise on the existing format of a sport, making it more attractive to the audience. Through such an exercise, they will understand how strategic changes to basic game formats can impact its success or failure. The case will encourage participants to think about viable business models for the revival of different types of sport.

Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

CSS 8: Marketing.

Motivated by the need for research on the relationship between health app usage and health-related outcomes in the form of health status and life satisfaction, this study builds on self-regulation theory to construct a research model for elucidating how health app quality affects health information literacy, health app usage and physical activity.

To empirically validate the proposed research model, a large-scale questionnaire survey on health app usage was administered on a sample of 6,948 respondents recruited from a university in China. Structural equation modeling was employed for data analysis.

Empirical findings demonstrate that health app quality positively affects self-regulation with respect to health app usage, health information literacy and physical activity. Taken together, these self-regulated behaviors drive health-related outcomes for health status and life satisfaction.

This study advances extant literature on health app usage through the application of self-regulation theory to investigate the effects of technological interventions in healthcare. Findings offer practical implications for how health apps can be leveraged to realize positive health-related outcomes.

The purpose of this paper is to examine how US school leaders make sense of external mandates, and the way in which their understanding of state and district accountability policies affects their work. It is posited that school leaders’ responses to external accountability are likely to reflect a complex interaction between their perception of the accountability policies, the state and district contexts in which those policies are situated and their own leadership beliefs and practices.

The authors use both principal and teacher survey data to explore the question of how perceptions of external policy are associated with instructional leadership behaviors. Cases of seven principals are employed to flesh out the findings from the survey analysis.

It is concluded that external accountability policy may have a positive impact on instructional leadership – where they see those policies as aligned with their own values and preferences, and where they see their district leaders as supportive of school‐driven accountability initiatives. In these cases, school leaders internalize the external accountability policies and shape them to the particular needs that they see as priorities in their own school. Where one or the other of these factors is weak or missing, on the other hand, leaders demonstrate more negative attitudes to external accountability and weaker instructional leadership.

This analysis draws on a unique, large‐scale data base and uses a mixed methods approach to answer the question.

This paper seeks to present a fully digital, real‐time (RT) hardware‐in‐the‐loop (HIL) simulator on PC‐cluster, of electric systems and drives for research and education purposes; to use the developed system to conduct several motor drives implementation and to evaluate the motor and the control algorithm performance in RT.

This simulator was developed with the aim of meeting the simulation needs of electromechanical drives and power electronics systems while solving the limitations of traditional RT simulators. This simulator has two main subsystems, software and hardware. The two subsystems were coordinated together to achieve the RT simulation. The software subsystem includes MATLAB/Simulink environment, a C++ compiler and RT shell. The hardware subsystem includes FPGA data acquisition card, the control board, the sensors, and the controlled motor.

The complexity of RT implementation of motor drives is greatly reduced by utilizing this simulator. The detailed operation and implementation of this simulator are presented, together with test results and comparisons with simulated virtual environment for a permanent magnet dc and induction motors (IM). The simulator performance is adequate for both open and closed loops motor drives. The simulation time step is limited by the system Master/Target CPU's speed, the communication network type, and the complexity of the control algorithm.

A typical application for this system is to select and evaluate the performance of electric motors for a hybrid electric vehicle in a real vehicle environment without actually installing that component in the real vehicle.

The use of the developed RT simulator to achieve HIL simulation allows rapid prototyping, converter‐inverter topologies testing, motors testing, and control strategies evaluation. The transition from simulated virtual environment to the HIL mode can be performed by replacing the model of the physical system (e.g. motor) with the DAQ blocks to represent the channels connected to the physical system sensors. The use of a single environment for both simulation and HIL control provides a quick experimentation and performance comparison between the real and simulated systems.

The purpose of this paper is to conduct the design, development and testing of a controller for an autonomous small‐scale helicopter.

The hardware in the loop simulation (HILS) platform is developed based on the nonlinear model of JR Voyager G‐260 small‐scale helicopter. Autonomous controllers are verified using the HILS environment prior to flight experiments.

The gains of the multi‐loop cascaded control architecture can be effectively optimized within the HILS environment. Various autonomous flight operations are achieved and it is demonstrated that the prediction from the simulations is in a good agreement with the result from the flight test.

The synthesized controller is effective for the particular test‐bed. For other small‐scale helicopters (with different size and engine specifications), the controller gains must be tuned again.

This work represents a practical control design and testing procedures for an autonomous small‐scale helicopter flight control. The autonomous helicopter can be used for various missions ranging from film making, agriculture and volcanic surveillance to power line inspection.

The research addresses the need for systematic design, development and testing of controller for a small‐scale autonomous helicopter by utilizing HILS environment.

The purpose of this paper is to develop an easily implemented and practical stabilizing strategy for the hardware-in-the-loop (HIL) system. As the status of HIL system in the ground verification experiment for space equipment keeps rising, the stability problems introduced by high stiffness of industrial robot and discretization of the system need to be solved ungently. Thus, the study of the system stability is essential and significant.

To study the system stability, a mathematical model is built on the basis of control circle. And root-locus and 3D root-locus method are applied to the model to figure out the relationship between system stability and system parameters.

The mathematical model works well in describing the HIL system in the process of capturing free-floating targets, and the stabilizing strategy can be adopted to improve the system dynamic characteristic which meets the needs of the practical application.

A method named 3D root-locus is extended from traditional root-locus method. And the improved method graphically displays the stability of the system under the influence of multivariable. And the strategy that stabilize the system with elastic component has a strong feasible and promotional value.

This study aims to assess tribal women’s health information literacy in their daily lives. The specific objectives are to determine the tribe’s interest and frequency of seeking health-related information, to know their preferred health information sources and health-care methods for treatment and to find out the prospective barriers to searching for and finding health-related information.

A well-structured questionnaire was designed and surveyed among the tribal women of Khagrachhari, Bandarban and Mymensingh districts in Bangladesh. Stratified sampling was used, and 326 responses were retrieved. The collected data were analyzed using Statistical Package for Social Sciences version 20 and Microsoft Excel.

Most of the tribal women are satisfied with their current health condition. Though they are highly interested in health-related information, they are very unusual in terms of searching for this kind of information. Vaccination information is their most desired information, and allopathic treatment is highly preferred by them. In this regard, they consult with doctors at nearby community clinics or government hospitals for different health issues. However, health information terminologies are often difficult for them to understand. High costs, lack of awareness and distance from health centers are significant barriers for tribal women seeking health-related information.

To the best of the authors’ knowledge, this is the first known effort in a developing country to study tribal women’s concerns regarding health-related issues.