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The aim of this paper is to find the regions of dynamic stability of systems of beams and frames with finite displacements and rotations. A suitable numerical procedure allows regions of dynamic stability to be obtained for any value of the dynamic force, taking into account the different characteristics of constraints, inertia and stiffness. A set of numerical applications is presented to show the capabilities of the proposed numerical method in the frame of the dynamic stability of beams.

This paper aims to present recently published resources on library instruction and information literacy providing an introductory overview and a selected annotated bibliography of publications covering all library types.

This paper introduces and annotates English-language periodical articles, monographs, dissertations, reports and other materials on library instruction and information literacy published in 2018.

The paper provides a brief description of all 422 sources, and highlights sources that contain unique or significant scholarly contributions.

The information may be used by librarians and anyone interested as a quick reference to literature on library instruction and information literacy.

The purpose of this paper is to show how to find the regions of dynamic instability of a beam axially loaded and visco‐elastically constrained at its ends by Kelvin‐Voigt translational and rotational units variously arranged according to different configurations, by using the equation of boundary frequencies.

With respect to visco‐elasticity the time variable is present as a parameter so that the above‐mentioned exact approach is exploited to draw three‐dimensional diagrams of the dynamic component of the periodic load and its frequency, varying with time and with the viscosity parameter μ characterizing the restraints.

For not rigidly constrained configurations a peculiar asymptotic tendency is recognizable in both cases.

The study allows for identifying the influence of visco‐elastic restraints in the response of a beam under a dynamic axial load. Dynamic excitation occurs in several fields of mechanics: dynamic loads are encountered in structural systems subjected to seismic action, aircraft structures under the load of a turbulent flow and industrial machines whose components transmit time‐dependant forces.

Visco‐elasticity accounts for possible vibration control solutions planned to improve the dynamic response of the rod; they can consist of layers of visco‐elastic material within the body of the modelled element or local viscous instruments affecting the boundary conditions; the latter is the application this paper focuses on.

With this paper a calculation procedure to get an exact solution for particular static configurations of the beam is followed in order to define the influence of visco‐elastic restraints under a dynamic axial load; the responses are given in terms of boundary frequencies domains and are supposed to be useful to learn the behaviour in time and in dependence of the intrinsic viscosity of the restraints.

The purpose of this paper is to investigate the bond behaviour between fiber reinforced polymer (FRP) sheets and concrete elements, starting from available experimental evidences, through a calibrated and upgraded 3D mathematical‐numerical model.

The complex mechanism of debonding/peeling failure of FRP reinforcement is studied within the context of damage mechanics to appropriately catch transversal effects and developing a more realistic and comprehensive study of the delamination process. The FE ABAQUS© code has been supplemented with a numerical procedure accounting for Mazars's damage law inside the contact algorithm.

It has been shown that such an approach is able to catch the delamination evolution during loading processes as well.

A Drucker‐Prager constitutive law is adopted for concrete whereas FRP elements are assumed to behave in a linear‐elastic manner, possibly undertaking large strains/displacements. Surface‐to‐surface contact conditions have been applied between FRP and adjacent concrete, including the enhancement given by the strain‐softening law according to Mazars' damage model. The procedure has been introduced to describe the coupled behaviour between concrete, FRP and adhesive resulting in specific bonding‐debonding features under different load levels.

Is there a sound philosophical foundation in the nature of professional activity for resolving the tension between altruism and self‐interest in favor of virtue and character? I believe there is, and I ground my proposal in six characteristics of the relationship of professionals to those who seek their help. Considered individually, none of these phenomena is unique in kind or degree. They may exist individually in other human relationships and occupations. But as a moral cluster they are, in fact, unique; they generate a kind of “internal morality”—a grounding for the ethics of the professions that is in some way impervious to vacillations in philosophical fashions, as well as social, economic, or political change. This internal morality explains why the ethics of medicine, for example, remained until two decades ago firmly rooted in the ethics of character and virtue, as were the ethics of the Hippocratic and Stoic schools. It is found in the seminal texts of Moslem, Jewish, and Christian medical moralists. It persisted in the eighteenth century in the writings of John Gregory, Thomas Percival, and Samuel Bard, who, although cognizant of the philosophies of Hobbes, Adam Smith, and Hume, nonetheless maintained the traditional dedication of the profession to the welfare of the patient and to a certain set of values. Only in the last two decades has there been—to use Hume's terms—a “sentiment of approbation” regarding self‐interest.

This paper studies the nonlinear dynamics of membrane structure considering wrinkling effect. The coupling between wrinkles and vibration is investigated elaborately, and new insight on the dynamics of wrinkled membrane is unveiled.

Based on the stability theory of plates and shells, the wrinkling model of the membrane structure is established. Considering the effects of wrinkling and nonlinearity, the dynamic response is calculated with NewMark method.

Wrinkling will impact the dynamics of the membrane structure significantly for asymmetrical tension loading cases, dynamic response of the wrinkled membrane structure can be classified into three categories: when the vibration is small, the dynamics of the wrinkled membrane structure will behave linearly, and the wrinkles will only affect the dynamic properties as initial conditions; when the vibration is relatively large, the wrinkles will interact with the vibration during the dynamic process, and the dynamics of the structure shows very complex features; when the vibration is large enough, the dynamics will be dominated by the geometric nonlinearity of large-amplitude vibration.

In the previous works on dynamics of wrinkled membrane structure, only the vibration modes have been studied, which means all those investigations are confined with linear vibration; little research has been conducted on the nonlinear dynamics of wrinkled membrane structure. In view of this, this paper presents an investigation of dynamic properties of membrane structure considering the wrinkling and geometric nonlinear effects. This research work presents some novel discoveries on the nonlinear dynamics of wrinkled membrane.

The resurgence of interest in professionalism necessarily focuses us on the moral core of medicine and the character of the good doctor. While medical education reform projects aimed at educating for professionalism are replete with lists of laudable virtues necessary for the doctor, we have made little progress in mapping those character traits, values and behaviors to admission procedures, curricular reform and faculty development. If educating for professionalism is to be effective, medicine must re-claim the moral core of professionalism and identify clearly the fundamental traits, values and virtues necessary for good medical practice in the twenty-first century.

Finds the regions of dynamic instability of elastic beams constrained at the ends by means of translational and rotational elastic springs, using the equation of boundary frequencies. Obtains the diagrams showing the regions of instability of the beam, as a function of the dynamic component of the periodic forcing function and its frequency, from that equation in exact form. In this procedure inertial, stiffness and constraint characteristics of the examined system are taken into account. Presents selected applications concerning the analysed problem.

The study examines the social and environmental responsibility indicators disclosed by three International Council on Mining and Metals (ICMM) corporate mining members in their social and environmental reporting (SER) from 2006 to 2014. To achieve this aim, the author limits the data two years before (i.e. from 2006 to 2007) and six years after (i.e. from 2009 to 2014) the implementation of the Sustainable Development Framework in the mining sector in 2008.

Using the techniques of content analysis and interpretive textual analysis, this study examines 27 social and environmental responsibility reports published between 2006 and 2014 by three ICMM corporate mining members. The study develops a disclosure index based on the earlier work of Hackston and Milne (1996), together with other disclosure items suggested in the extant literature and considered appropriate for this work. The disclosure index for this study comprised six disclosure categories (“employee”, “environment”, “community involvement”, “energy”, “governance” and “general”). In each of the six disclosure categories, only 10 disclosure items were chosen and that results in 60 disclosure items.

A total of 830 out of a maximum of 1,620 social and environmental responsibility indicators, representing 51% (168 employees, 151 environmental, 145 community involvement, 128 energy, 127 governance and 111 general) were identified and examined in company SER. The study showed that the sample companies relied on multiple strategies for managing pragmatic legitimacy and moral legitimacy via disclosures. Such practices raise questions regarding company-specific disclosure policies and their possible links to the quality/quantity of their disclosures. The findings suggest that managers of mining companies may opt for “cherry-picking” and/or capitalise on events for reporting purposes as well as refocus on company-specific issues of priority in their disclosures. While such practices may appear appropriate and/or timely to meet stakeholders’ needs and interests, they may work against the development of comprehensive reports due to the multiple strategies adopted to manage pragmatic and moral legitimacy.

A limitation of this research is that the author relied on self-reported corporate disclosures, as opposed to verifying the activities associated with the claims by the sample mining companies.

The findings from this research will help future social and environmental accounting researchers to operationalise Suchman’s typology of legitimacy in other contexts.

With growing large-scale mining activity, potential social and environmental footprints are obviously far from being socially acceptable. Powerful and legitimacy-conferring stakeholders are likely to disapprove such mining activity and reconsider their support, which may threaten the survival of the mining company and also create a legitimacy threat for the whole mining industry.

This study innovates by focusing on Suchman’s (1995) typology of legitimacy framework to interpret SER in an industry characterised by potential social and environmental footprints – the mining industry.

The purpose of this paper is to use symmetry conditions for the reduction of computing times in problems involving finite element‐based multi‐scale constitutive models of nonlinear heterogeneous media.

Two types of representative volume element (RVE) symmetry often found in practice are considered: staggered‐translational and point symmetry. These are analyzed under three types RVE of kinematical constraints: periodic boundary fluctuations (typical of periodic media), linear boundary displacements (which gives an upper bound for the macroscopic stiffness) and the minimum kinematical constraint (corresponding to uniform boundary tractions and providing a lower bound for the macroscopic stiffness).

Numerical examples show that substantial savings in computing times are achieved by taking advantage of such symmetries. These are particularly pronounced in fully coupled two‐scale analyses, where the macroscopic equilibrium problem is solved simultaneously with a large number of microscopic equilibrium problems at Gauss‐point level. Speed‐up factors in excess of seven have been found in such cases, when both symmetry conditions considered are present at the same time.

This paper extends the original considerations of Ohno et al. to account for other RVE kinematical constraints, namely, the linear boundary displacement and the minimum kinematical constraint (or uniform boundary traction model). Provides a more precise assessment of the impact of the use of such symmetries on computing times by means of numerical examples. In addition, for completeness, the direct enforcement of such constraints within a Newton‐based finite element solution procedure for the RVE equilibrium problem is detailed in the paper.