Nonconservative Nature of the Stresses Developed in a Continuum.

The stresses in an elastic continuum (i.e. a continuum with zero strains after unloading) are classically deemed to be conservative (i.e. their total work all over the continuum is a single-valued function of only the displacement distribution in the continuum). So, internal damping in an elastic continuum appears to be a contradiction in itself. Actually, the total work of the internal stresses all over a continuum does not coincide with the strain energy of the continuum, but also includes the work of the internal body forces formed by the stress derivatives, which only con-tributes to the kinetic energy of the continuum. Owing to this inclusion, the total work of the internal stresses cannot be a single-valued function of only the displacement distribution in the continuum, and hence, the internal stresses must be nonconservative, which indicates internal damping inherent in any continuum whether elastic or not. Only statically deforming continua may possess conservative internal stresses

Bernoulli's Transformation of the Response of an Elastic Body and Damping

Bernoulli's transformation and the related separation of variables method or modal analysis as classically applied to the partial differential equation of motion of an elastic continuum will always conclude an undamped response. However, this conclusion lacks reliability, since the underlying analysis assumes either integrandwise differentiability (i.e. differentiation and integration signs are interchangeable) or termwise differentiability (i.e. the derivative of an infinite series of terms equals the sum of the derivatives of the terms) for Bernoulli's transformation, which not only is responsible for the undamped response but also is arbitrary. This paper using Bernoulli's transformation examines an elastic uniform column ruled by the generalized Hooke’s law and subjected to axial surface tractions at its free end or a free axial vibration, and shows that the above differentiability assumptions underlying classical analysis are equivalent and actually constitute a limitation to the class of the response functions. Only on this limitation, damping appears to be inconsistent with the elastic column response. Removing the limitation through nontermwise differentiability of Bernoulli’s transformation results in a damped response of the elastic column, which indicates that damping actually complies with the generalized Hooke’s law as applied to elastic continua

Examining the Attitudes, Pro-Social Value Orientations and Social Norms of Older People to Road Pricing

This study is set to investigate the relationship between older age and the acceptability of road pricing. Specifically, it examines the attitudes of the people aged 60 and over to road pricing in comparison with the attitudes of younger people using relevant literature review findings, secondary data analysis and the results of a questionnaire and three group discussions. Moreover, this research examines whether older people’s support for what is positively valued for society affects these attitudes. Older people are more likely to express positive or negative opinions about road pricing depending on whether they believe it would be good or bad for others, or society. The influence that family, friends or others in general may have on people’s beliefs about road pricing is another subject that is examined. By looking into these issues this work highlights some of the potential opportunities and problems in the present context of the acceptability of road pricing. This will hopefully help policy-makers to decide on actual design criteria and consultation mechanisms that could assist in promoting and communicating better road pricing to older people, making it publicly and therefore politically more acceptable

Road Pricing and Older People: Identifying Age-Specific Differences Between Older and Younger People's Attitudes, Social Norms and Pro-Social Value Orientations to Road Pricing.

The implementation of road pricing schemes is likely to be an inescapable measure in the future of managing road transport demand in highly congested environments. Since public acceptability is the ‘Holy Grail’ of charging policy-making, revealing the special attitudinal issues of older people may help the identification of some of the potential social dilemmas of road pricing. In an ageing society, where older people have a growing influence in politics in general, and potentially in the acceptability of road pricing in particular, their attitudes to road pricing are of particular interest because they face specific types of risk of transport-related social exclusion. Moreover, older people favour, more than any other age groups, what is positively valued for society – a process termed as ‘pro-social value orientation’. Hence in a transport context, older people may be more likely to express positive or negative attitudes to the acceptability of road pricing depending on whether they believe it would be good or bad for others, or society in general. Family and friends may also have a particular influence on older people’s evaluations about their intentions and choices - thus the importance of studying the influence of ‘social norms’ on older people’s attitudes to road pricing. The paper will develop a thorough theoretical and empirical understanding of these issues, based on the findings of a primarily quantitatively-assessed survey of 491 post-back responses combined with secondary data analysis. This will lead to the identification of age-specific differences of public attitudes to road pricing. All in all, some support is provided for the view that attitudes to road pricing do vary with age as pro-social value orientations, social norms and their influence on attitudes also do

Bike-Sharing: Is Safety an Issue Adversely Affecting its Potential for Being Embraced by Urban Societies?

Using bicycles on an ‘as-needed’ basis, usually for a small rental fee and without the externalities and obligations linked to bicycle ownership, is what makes public bicycles a societally affordable medium to enhance the transition to a more sustainable urban transport paradigm. However, despite its distinctive character in terms of its potential to be a mechanism transforming in some degree urban mobility to a shared responsibility regime, bike-sharing still faces some of the same safety concerns associated with ordinary bicycle ridership. The most common problem for cyclists’ wellbeing is that the traffic system is designed predominately from a car-user perspective. Even the cities that have recently implemented public bicycle programmes, and therefore showed some extra care to provide fitting urban conditions for them, have not yet achieved to fully eclipse car-orientation as the prime cornerstone of their development norms. This means that transport systems worldwide do not necessarily take fully into account the main characteristics of cyclists reflecting safety themes: a cyclist is vulnerable (in a crash), flexible (in behaviour), instable (may fall off the bike), inconspicuous (difficult to see), has differing abilities (due to a wide range of the population), is conscious of effort (i.e., highly motivated to minimize energy expenditure), and sometimes seen as intruders in the traffic systems, rather than as an integral part. This work refers to the results of a research scheme that meant to examine road users’ attitudes directly reflecting public acceptability towards two bike-sharing schemes in Drama (Greece, 50.000 residents) and Gothenburg (Sweden, 500.000 residents). Although safety was not the principal initiative for doing this dual study, one key conclusion was that many people could not embrace bike-sharing due to their perceptions that bicycle represents in general an unsafe travel mode and that their cities provide only limited road safety for cyclists

The Many Lives — and Faces — of Lex Mercatoria: History as Genealogy in International Business Law

It has been claimed that cross-border business transactions are governed by a transnational body of norms specific to international trade, generally known as lex mercatoria, the law merchant. This legal phenomenon is in fact often described as the new lex mercatoria, as distinguished from the ancient law merchant, which purportedly flourished in medieval and early modern Europe. Here, Hatzimihail discusses about lex mercatoria, which has been variously described by its advocates as a set of general principles and customary rules spontaneously referred to or elaborated in the framework of international trade

Gradualism and Uncertainty in International Union Formation

This paper introduces a new theoretical framework of international unions qua coalitions of countries adopting a common policy and common supranational institutions. We introduce a general class of non-cooperative spatial bargaining games of coalition formation among three countries in order to examine the endogenous strategic considerations in the creation and enlargement of international unions. Why would we observe a gradualist approach in the formation of the grand coalition even if the latter is assumed to be weakly efficient? We propose uncertainty about the benefits of integration as a mechanism that can generate gradual union formation in equilibrium. As it turns out, it may well be in the ‘core’ countries’ interest to delay the accession of a third, peripheral country in order to i) stack the institutional make-up of the initial union in their favor and ii) signal their high resolve to wait out the expansion of their bilateral subunion. A related case from the European Union provides an interesting illustration.