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An analysis is made or the basic principles which govern the operation of those air‐cushion devices otherwise known as ground‐effect machines (GEMs). Most of these vehicles can be defined as machines which operate in close proximity to the earth's surface without ever physically touching it because they are always separated from it by a cushion or a layer of air, however thin; as a consequence, propulsion and control of GEMs must be of an aerodynamic nature. The only machines not covered by this definition are special types of over‐water GEMs. It is proposed to establish six main categories of GEMs from which all other possible configurations could be evolved by proper combination of the basic types. For each of these six configurations, a critical biographical survey is made and some comparative features are pointed out. The overall picture is one of great complexity because of the large number of parameters involved. This points out the danger of a ‘hardware’ approach to the GEM problem until a firm base of comprehensive research has been established. At the present time, the emphasis placed on the annular jet seems justified, inasmuch as the annular jet represents a good compromise between versatility, simplicity and performance.

Cycloidal rotors, also known as cyclogyros, are horizontal axis rotary-wing machines with potential for Vertical Take-Off and Landing aircraft applications. The paper aims to devise and validate a new semi-empirical analytical model that is capable of assisting in the structural and aerodynamic design of cyclogyros.

The analytical model comprises a purely analytical kinematic sub-component that is used for analyzing the structural feasibility of the rotor. Several geometrical parameters are assessed, e.g. the oscillation schedule of the blades as a function of the properties of the pitching mechanical system. The dynamic sub-component of the model is used for estimating the rotor thrust production and power consumption. This sub-component is semi-empirical and uses a calibration function that was devised using the available experimental data.

For a set of initial conditions and geometrical parameters, the model is capable of providing a real animation of the cyclogyro operation. It is shown that the motion of the blades does not comply with the requirements of a perfect cycloidal curve. The study concerning the simulation of the virtual camber effect on the drum blades, with and without the pitch effect, shows that the virtual camber strongly depends on the chord-to-radius ratio and on the aircraft advance velocity.

A new analytical model capable of assisting in the geometrical and aerodynamic design of cyclogyros is here proposed. The model is capable of providing approximate estimations of the cyclogyro thrust production and power consumption under operating design conditions.

The effect of moncyclic versus polycyclic aromatic components in JP‐5 fuels, on total flame radiant energy was investigated. Variations in aromatic type and content within the JP‐5 specification had an effect on flame radiation. Polycyclic aromatic fuel blends burn with higher flame emissivities than the monocyclic blends of comparable ASTM Smoke Point. Radiant heating of metal parts was shown to be a function of their location in the combustion chamber. The use of low‐luminosity fuels gave major reductions in liner temperatures in the J‐57 combustion chamber.

TWENTY years ago the phenomenon of ground‐effect was known and to some extent understood but at the same time regarded generally with some misgivings. An aircraft in close proximity to the ground was often found to have lift capabilities far in excess of those evident at higher altitudes and this was attributed to the air ‘trapped’ between the aircraft and the ground. To the student pilot attempting a three‐point landing at a predetermined spot on the runway the tendency for the aeroplane with flap down to float on interminably was all too easily attributed to ground‐effect. This feature, embodied in the ram wing, was one portent of a number of air‐riding vehicles that certain far‐sighted men recognized as having tremendous potential. More recently it has become increasingly apparent that the ground‐effect phenomenon has a definite application to transportation and many countries are actively pursuing research and development investigations regarding the choice of the most suitable system.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.

Motivation significantly influences learning and memory. While a long history of research has focused on simple forms of associative learning, such as Pavlovian conditioning, recent research is beginning to characterize how motivation influences episodic memory. In this chapter we synthesize findings across behavioral, cognitive, and educational neuroscience to characterize motivation’s influence on memory. We provide evidence that neural systems underlying motivation, namely the mesolimbic dopamine system, interact with and facilitate activity within systems underlying episodic memory, centered on the medial temporal lobes. We focus on two mechanisms of episodic memory enhancement: encoding and consolidation. Together, the reviewed research supports an adaptive model of memory in which an individual’s motivational state (i.e., learning under states of reward or punishment) shapes the nature of memory representations in service of future goals. The impact of motivation on learning and memory, therefore, has very clear implications for and applications to educational settings.

To show that Chinese consumers are constantly redefining and revaluing goods along the axes of the real and the false, with little regard for legal definitions of brand authenticity or “fakeness.”

The data was collected through interviews, focus groups, observations, and casual conversations over 16 months of ethnographic research in Beijing, China.

In their everyday consumption practices and navigation of a complex and often dangerous marketplace, Chinese consumers categorize products based on their perceived “truth.” The paper introduces a typology that describes these local categories and explains their utility for consumers.

The data was primarily conducted in an urban capital with a highly educated and high-average-income populace, thus it does not represent all Chinese consumers or a statistical sample.

This paper explains how the same globalizing processes that helped brands establish themselves in the Chinese market now threaten the capability of all brands to gain and retain the trust of consumers

By explaining how new calculations of value are being produced under glocalized regimes of manufacture and distribution, this research makes an important contribution to our understandings of brands and their limits.

Emerging from the COVID-19 pandemic, the Philippines has undergone the “new normal” transition, creating a strategic recovery effort to reinvigorate the industry. In tourism, these transitions aim to safeguard employees' and guests' health and safety, ensure continuity of business operations, boost tourism confidence leading to satisfaction, and establish a resilient and sustainable tourism industry in the postpandemic era. Hence, this chapter employs a system thinking leveraging a causal loop diagram (CLD) to construct a comprehensive roadmap for Philippine tourism's postpandemic resurgence through the system thinking lens. The CLD visually illustrates the inter-related factors influencing the recovery process, encompassing collaborative engagements, innovations, economic revitalization, and health and safety protocols. By analyzing the causal relationships among these variables, this chapter explicates the dynamic and interconnected nature of the postpandemic recovery leading to the recovery of the Philippine tourism industry, especially in the context of thinking small. Through this chapter, thinking small could involve a shift toward localized solutions and community-focused initiatives that allow them to foster local economies, build resilience, and create a more inclusive and sustainable postpandemic recovery.