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This paper aims to present new analytical expressions for the mutual inductance and forces between non-coaxial co-planar circular thin-wall air coils.

The expressions are based on an integration method found in the literature, so far used only to describe mutual inductances. It is new to apply this method as a starting point to get the forces between non-coaxial co-planar rings and coils. The approach is further extended to include non-coaxial co-planar thin-wall cylindrical coils.

This new method enables interaction modelling between coils by solving integrals numerically, covering fully, partially and non-overlapping coils in a single form. The expressions are verified by comparing the results with alternatives methods.

The forces and mutual inductances of non-coaxial co-planar circular coils are obtained with analytical expressions, fitted well for optimization studies. The study is limited to coils in free air.

A typical application is the interaction between coils in a wireless energy transfer system (as applied for battery loading for mobile phones and automotive). The expressions can be used to also predict the forces between two non-coaxial disk or ring magnets as used in magnetic levitation systems.

Maxwell described the coupling between two coaxial co-planar rings, and steadily more and more equations describing the interaction between circular coils became available in the past decades. The target of this study is to obtain compact equations for non-coaxial co-planar circular coils. This is realized with the combination of existing literature and mathematical modelling tools.

The calculation of forces between rectangular conductors with a uniform current density as can be found in the long coils as used in linear actuators and planar motors.

The proposed methodology relies on a single analytical equation that is used to compute all the force components.

Several comparisons with other available techniques are provided. All the comparisons confirm the validity of the proposed analytical method.

In the literature, other analytical methods for the force computation can be found. However, these often have limitations (e.g. only adjacent conductors or non-adjacent conductors). This paper adds a new compact expression that covers all the possible configurations at the same time. This new tool holds for all the analytical expression found in the literature.

This paper reports on how prospective users may be involved in the design of entertaining educational computer games. The paper illustrates an approach, which combines traditional Participatory Design methods in an applicable way for this type of design. Results illuminate the users’ important contribution during game development, especially when intended for a specific target group. Unless prospective members of the target group are consulted it is difficult to foresee opinions of game content, aesthetics and the overall game experience of the users ‐ aspects very much included or at least related to the theoretical concept of intrinsic motivation. Whereas pedagogical experts can contribute with learning content, the users are the ones who can state what is actually fun or not. Users’ participation during the design process enables development of games that are directed to the learners and their expectations. The researchers collaborated with a multimedia design team in development of an educational web‐based computer game, developed for the Swedish Broadcasting Corporation.

The purpose of this paper is to explore eighteenth‐century London retailers' attitudes to shoplifting and their strategies for countering customer theft.

The paper is based on an examination of contemporary documentary evidence, in particular a quantitative and qualitative analysis of shopkeeper practice drawn from trial transcripts of shoplifting prosecutions at London's highest criminal court, the Old Bailey.

The paper reveals that shopkeepers predominantly invested in preventative measures to control customer theft, rather than relying on prosecution. It demonstrates that improved shop fittings and new marketing methods served to reinforce the effectiveness of this strategy. The techniques that retailers employed are shown to directly reflect the nature and location of the risks they experienced, even to the extent of being a contributory factor in the withdrawal of women from the retail sector during this period.

The study is limited to a sample of London trials and the experiences of retailers who prosecuted.

This is the first study of shoplifting prevention in this period. It analyses retailer practice and illustrates how this interacted with their perception of the prevalence of criminality, demonstrating that their approach to stock protection anticipated that of modern retailers. It complements existing scholarship on eighteenth‐century retailing and marketing.

This chapter deals with the development of banking in the Crown of Aragon from the end of the thirteenth century through the establishment of money changers, which followed similar patterns as in other Western European territories. It starts with a review of existing literature and follows with an explanation on the different banking services provided by money changers and the specific legal framework that supported such activities. It then examines the geographical distribution of private banks in cities and towns within the domains of the kings of Aragon, as well as their evolution throughout the fourteenth century. After that, it offers an analysis of the most common professional profiles among these bankers and financers. Finally, drawing on a heterogeneous pool of unpublished data, it seeks to shed light on the diversity of investors and clients of these establishments, a crucial proof of their role in integrated financial markets.

Globalisation and Tourism. Vom 22. bis 28. September 1996 fand in Rotorua (Neuseeland) der 46. Kongress der AIEST statt. Kolleginnen und Kollegen aus fünf Kontinenten und 14 Ländern befassten sich in ihren Referaten mit den Auswirkungen des Globalisierungsprozesses auf die Märkte, die Produktionsbedingungen, die Unternehmensstrukturen, die Standorte und die Kulturen.

Metropolitan miseries ‐ 1 City of Westminster. We received in November a short sharp letter signed by most of the library staff protesting about cuts in the service. These were attributed to ‘one man's report’, a citation vague enough to account for a mild grumble from Barnes (M). ‘Trouble is’, he said in some sorrow, ‘they think it was my report.’ It wasn't. It was the doing of a councillior now elevated to chair the committee to run (down) the library service. Further misery: Harrison (K C) is reported to have bewailed the disappearance of the title ‘City Librarian’, for when Barnes (M) goes the library service gets submerged in a leisure directorate. Barnes (M) is now (at the time of reading) Guildhall Librarian, City of London. They have their own miseries there, but they are well gilded and guilded by centuries of mediaeval floohflah under a heavy top dressing of well‐established City ways with money and the making thereof. And in case you haven't noticed, the City of London is listed with all those naughty places like Hackney and Sheffield and the glc as an over‐spending local authority. It's enough to make City Common Councilmen stand guard at Temple Bar and turn back ministers and royal persons.

“Motivation” is one of those words that is commonly used to describe the fuzzy notion of “why we do what we do.” There are numerous ironies about motivation that make the topic all the more difficult to understand. By examining these ironies more closely, we can avoid their pitfalls. Following, then, are what I consider the top ten ironies of motivation.

Allemagne: l'expérience TOUROPA Amorcée dès 1932 par le Docteur Vegetier de Berlin, l'expérience de voyages collectifs fut reprise et développée dès la fin de la Deuxième Guerre mondiale. A cette fin fut créée, en 1948, la société TOUROPA. Au départ, le capital était constitué de la manière suivante:

Pour différentes raisons, une place de plus en plus dominante est attribuée au tourisme dans le cadre du développement économique. Depuis quelques années déjà les pays touristiques européens dits «classiques» se voient confrontés avec des concurrents, points blancs sur les cartes touristiques il y a quelques années seulement. Les grands organisateurs de voyages européens proposent aujourd'hui au public des régions touristiques au cachet encore extraordinaire et parfois même aventureux mais qui demain seront fréquentées par tous les milieux. Il est fort possible que, dans un avenir très proche, le Sahara, l'Amazonie ou l'Himalaya soient aménagés en stations touristiques très confortables.