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J.R.D. Kenward was with British Airways from 1950–1977: as Manager, Performance Engineering from 1967: from 1947–50, he was with BOAC in various technical branch posts. After graduation he entered the design office of De Havilland 1946–7. Since 1977 he has been a Consultant in aviation.

In this chapter we review the recent and growing literature on medium-term growth patterns. This strand of research emerged from the realization that for most countries economic development is a highly unstable process; over a course of a few decades, a typical country enjoys periods of rapid growth as well episodes of stagnation and economic decline. This approach highlights the complex nature of growth and implies that studying transitions between periods of fast growth, stagnation, and collapse is essential for understanding the process of long run growth. We document recent efforts to characterize and study such growth transitions. We also update and extend some of our earlier research. Specifically, we use historical data from Maddison to confirm a link between political institutions and propensity to experience large swings in growth. We also study the role of institutions and macroeconomic policies, such as inflation, openness to trade, size of government, and real exchange rate overvaluation, in the context of growth transitions. We find surprisingly complex effects of some policies. For example, trade makes fast growth more likely but also increases the frequency of crises. The size of government reduces the likelihood of fast miracle-like growth while at the same time limiting the risk of stagnation. Moreover, these effects are nonlinear and dependent on the quality of institutions. We conclude by highlighting potentially promising areas for future research.

Basic safety message (BSM) is a core subset of standard protocols for connected vehicle system to transmit related safety information via vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I). Although some safety prototypes of connected vehicle have been proposed with effective strategies, few of them are fully evaluated in terms of the significance of BSM messages on performance of safety applications when in emergency.

To address this problem, a data fusion method is proposed to capture the vehicle crash risk by extracting critical information from raw BSMs data, such as driver volition, vehicle speed, hard accelerations and braking. Thereafter, a classification model based on information-entropy and variable precision rough set (VPRS) is used for assessing the instantaneous driving safety by fusing the BSMs data from field test, and predicting the vehicle crash risk level with the driver emergency maneuvers in the next short term.

The findings and implications are discussed for developing an improved warning and driving assistant system by using BSMs messages.

The findings of this study are relevant to incorporation of alerts, warnings and control assists in V2V applications of connected vehicles. Such applications can help drivers identify situations where surrounding drivers are volatile, and they may avoid dangers by taking defensive actions.

This paper aims to introduce novel linear synchronous motor (LSM) driven assembly automation and material handling system designs with examples.

Discusses novel LSM technology principles with some practical system design and configuration examples for automated assembly and material handling. The high energy density and rugged design offers high duty cycle, high power, rapid acceleration, improved speed, high positioning repeatability, and increased performance for demanding installations.

LSMs can increase throughput, reliability and payload information feedback. They can also decrease maintenance requirements, and the total cost of installation. MagneMotion's patented QuickStick system propels and controls each vehicle independently by interacting with a permanent magnet array mounted to each vehicle. As a consequence, the vehicles do not require communication or power cables, allowing a broad range of flexible, reconfigurable configurations and move profiles.

LSMs can increase throughput, reliability and payload information feedback. They can also decrease maintenance requirements, and the total cost of installation.

Discusses novel LSM technology principles with some practical system design and configuration examples for automated assembly and material handling.

This paper aims to describe a novel hybrid inertial measurement unit (IMU) for motion capturing via a new configuration of strategically distributed inertial sensors, and a calibration approach for the accelerometer and gyroscope sensors mounted in a flight vehicle motion tracker built on the inertial navigation system.

The hybrid-IMU is designed with five accelerometers and one auxiliary gyroscope instead of the accelerometer and gyroscope triads in the conventional IMU.

Simulation studies for tracking with both attitude angles and translational movement of a flight vehicle are conducted to illustrate the effectiveness of the proposed method.

The cross-quadratic terms of angular velocity are selected to process the direct measurements of angular velocities of body frame and to avoid the integration of angular acceleration vector compared with gyro-free configuration based on only accelerometers. The inertial sensors are selected from the commercial microelectromechanical system devices to realize its low-cost applications.

Improvements in both robot manufacture and robot controller technology have resulted in greater robot accuracy. A trial has been conducted to highlight the improvements brought by this evolution. By measuring the accuracy of the velocity profiles of two generations of the Fanuc Hexapod robot (the Flextool), these evolutionary developments are illustrated. The results from the trial show that although both generations of robot exhibit good accuracy, the later robot is superior both in terms of mechanical design and in controller processing capability.

This study aims to a launchable design has been made to prevent wasted time in time-critical areas, and increase the efficiency of the unmanned aerial vehicle (UAV). In this way, a UAV can reach the mission height quickly.

A unique launchable UAV and launcher mechanism have been designed. The launchable UAV will be folded into the launcher mechanism and will automatically start flight after launch. The study includes mathematical calculations, 3D designs steps and produced UAV tests for the designed UAV. The launcher mechanism was designed in accordance with the tests for the UAV, and appropriate choices were made for the altitude and launch acceleration required by the UAV. According to the calculations, material selection and production were made.

In the tests, the climbing time was reduced by 1 s compared with the existing UAVs. With the launch, it enabled it to reach the altitude quickly and silently. In addition, because the launch energy was provided externally, it provided an advantage for the flight time.

A rotary-wing UAV with a launch mechanism and a fast launch was designed and prototyped. The maximum climb speed of the designed drone is 6.52 m/s. Frame arm length is 9.2 cm, propeller diameter is 15.24 cm and hover flight time is 7.2 m.

The UAV design can be launched. Design, calculation and experimental studies have been carried out for rapid take-off of the rotary wing UAV. The parts used in the UAV are originally produced. It is not a commercial product.

The purpose of this paper is to experimentally and numerically study the transient hydraulic impact and overall performance during startup accelerating process of mixed-flow pump.

In this study, the impeller rotor vibration characteristics during the starting period under the action of fluid–structure interaction was investigated, which is based on the bidirectional synchronization cooperative solving method for the flow field and impeller structural response of the mixed-flow pump. Experimental transient external characteristic and the transient dimensionless head results were compared with the numerical calculation results, to validate the accuracy of numerical calculation method. Besides, the deformation and dynamic stress distribution of the blade under the stable rotating speed and accelerating condition were studied based on the bidirectional fluid–structure interaction.

The results show that the combined action of complex hydrodynamic environment and impeller centrifugal force in the startup accelerating process makes the deformation and dynamic stress of blade have the rising trend of reciprocating oscillation. At the end of acceleration, the stress and strain appear as transient peak values and the transient effect is nonignorable. The starting acceleration has a great impact on the deformation and dynamic stress of blade, and the maximum deformation near the rim of impeller outlet edge increases 5 per cent above the stable condition. The maximum stress value increases by about 68.7 per cent more than the steady-state condition at the impeller outlet edge near the hub. The quick change of rotating speed makes the vibration problem around the blade tip area more serious, and then it takes the excessive stress concentration and destruction at the blade root.

This study provides basis and reference for the safety operation of pumps during starting period

The general impression formed by the second edition of the Business Ratio Report on Paint and Printing Ink Manufacturers is of rapid acceleration in terms of sales and in terms of profitability. This must, for the major part, have been due to the well‐documented boom in house building (as was) and in the do‐it‐yourself market.