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Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years. The finite element method has been widely used to solve contact problems with various grades of complexity. Great progress has been made on both theoretical studies and engineering applications. This paper reviews some of the main developments in contact theories and finite element solution techniques for static contact problems. Classical and variational formulations of the problem are first given and then finite element solution techniques are reviewed. Available constraint methods, friction laws and contact searching algorithms are also briefly described. At the end of the paper, a bibliography is included, listing about seven hundred papers which are related to static contact problems and have been published in various journals and conference proceedings from 1976.

This paper aims to examine the measurement of intangible aspects of research and development (R&D) projects, particularly from the funding organization's point‐of‐view.

A literature review on R&D measurement is carried out in order to identify the intangible factors to be measured as well as potential indicators. The practical applicability of the measures is discussed in light of an exploratory case study.

Lists of intangible inputs and outputs of R&D projects are presented along with some potential measures. The assessment of the intangible aspects of R&D projects is considered important for the funding organization. However, the current measurement practices are inadequate.

The results provide a summary of the current status of the topic and a basis for further research.

The knowledge about the intangible aspects of R&D projects summarized in this paper has been scattered before in a wide set of previous research literature. The evaluation of the existing measures provides valuable information for understanding the development stage of this academic and managerial discipline.

The purpose of this paper is to describe the work of IDMEC, a not‐for‐profit R&D private association located in Porto and Lisbon, Portugal.

The paper focuses on IDMEC's R&D activities, focusing on aeronautics.

Together IDMEC‐Porto and INEGI provide answers to R&D challenges in the broad area of aerostructures, from fracture and fatigue problems to advanced composites for space applications.

The paper offers a concise presentation of the IDMEC's R&D activities in the field of aeronautics.

This study examines social responsibility information disclosure on the Internet by Portuguese listed companies in 2003 and also analyses annual reports as a disclosure medium for those companies which disclose such information on their web pages. The results are interpreted through the lens of legitimacy theory, according to which companies disclose social responsibility information to present a socially responsible image so that they can legitimise their behaviours to their stakeholder groups. Companies in sectors that have a larger potential impact on the environment or in industries with a high visibility among consumers seem to exhibit greater concern to improve the corporate image through social responsibility information disclosure. Results thus suggest that legitimacy theory may be an explanation of social responsibility disclosure by Portuguese listed companies.

The problem of damage and crack detection in structural components has acquired an important role in recent years. Since the presence of cracks in a structure may alter its vibrational characteristics, the estimation of such variations can be used to detect cracks and damage, and to monitor the integrity of structures. The use of fast, easy and inexpensive non‐destructive testing is thus a major task. In this paper, sensitivity analysis by measurement of the reduction of eigenfrequencies was utilized to localize a crack in a non‐rotating shaft coupled to an elastic foundation. The shaft was modeled by the finite element method and coupled to an experimentally identified foundation model. The detection of a crack with different depths and orientations was verified experimentally and a good agreement between actual and detected crack positions was achieved. Finally easiness, effectiveness, applicability of the method and its extensions are also shown.

OUR readers will, we trust, appreciate our double souvenir number issued in connection with the Library Association Conference at Glasgow. Special features are the articles on the Mitchell Library, Glasgow, 1874–1924, by a member of the staff, Mr. J. Dunlop, and one on the Burns Country, by Mr. J. M. Leighton, of Greenock Public Library. We printed the provisional programme in our July issue and as we go to press have little to add to the particulars there given, except to compliment the Library Association and the Local Reception Committee on the excellent programme arranged for the occasion, from both the professional and social point of view.

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

The purpose of this paper is to evaluate and exploit the combination of additive manufacturing polymeric technology and structural adhesives. The main advantage is to expand the maximum dimension of the 3D printed parts, which is typically limited, by joining the parts with structural adhesive, without losing strength and stiffness and keeping the major asset of polymeric 3 D printing: freedom of shape of the system and low cost of parts.

The materials used in the paper are the following. The adhesive considered is a commercial inexpensive acrylic, quite similar to superglue, applicable with almost no surface preparation and fast curing, as time constraint is one of the key problems that affects industrial adhesive applications. The 3D printed parts were in acrylonitrile butadiene styrene (ABS), obtained with a Fortus 250mc FDM machine, from Stratasys. The work first compares flat overlap joint with joints designed to permit mechanical interlocking of the adherends and then to a monolithic component with the same geometry. Single lap, joggle lap and double lap joints are the configurations experimentally characterized following a design of experiment approach.

The results show a failure in the substrate, due to the low strength of the polymeric adherends for the first batch of typical bonded configurations, single lap, joggle lap and double lap. The central bonded area, with an increased global thickness, never does fail, and the adhesive is able to transfer the load both with and without mechanical interlocking. An additional set of scarf joints was also tested to promote adhesive failure as well as to retrieve the adhesive strength in this application. The results shows that bonding of polymeric AM parts is able to express its full potential compared with a monolithic solution even though the joint fails prematurely in the adherend due to the bending stresses and the notches present in the lap joints.

Because of the 3D printed polymeric material adopted, the results may be generalized only when the elastic properties of the adherends and of the adhesive are similar, so it is not possible to extend the findings of the work to metallic additive manufactured components.

The paper shows that the adhesives are feasible way to expand the potentiality of 3 D printed equipment to obtain larger parts with equivalent mechanical properties. The paper also shows that the scarf joint, which fails in the adhesive first, can be used to extract information about the adhesive strength, useful for the designers which have to combine adhesive and additive manufactured polymeric parts.

To the best of the researchers’ knowledge, there are scarce quantitative information in technical literature about the performance of additive manufactured parts in combination with structural adhesives and this work provides an insight on this interesting subject. This manuscript provides a feasible way of using rapid prototyping techniques in combination with adhesive bonding to fully exploit the additive manufacturing capability and to create large and cost-effective 3 D printed parts.

This study aims to investigate the impact of ownership structure and board structure on risk-taking as measured by research and development (R&D) Intensity in OECD countries.

A panel data of 300 companies from Anglo American and European countries between 2010 and 2016 were used. The ordinary least square multiple regression analysis procedure is used to examine the relationships. The findings are robust to alternative measures and endogeneities.

The results show that institutional ownership, board size, independent directors and board diversity are negatively related to risk-taking, with greater significance among Anglo American countries than among Continental European countries. In contrast, the results show that director ownership is statistically insignificant.

This study extends and contributes to the extant corporate governance (CG) literature, by offering new evidence on the effect of ownership and board structure on risk-taking between two different traditions. The findings will help regulators and policy-makers in the OECD countries in evaluating the adequacy of the current CG reforms to prevent management misconduct and scandals. These findings are relevant for companies aiming to adopt the most suitable governance mechanisms to pursue their R&D objectives and for policymakers interested in promoting R&D investment.

The purpose of this paper is to analyze the relationship between the ownership structure and the investment in research and development (R&D) for a sample of listed Spanish companies.

Following the agency theory and the socioemotional wealth (SEW) perspective, the authors propose that R&D investment is affected by ownership structure, specifically by the identity of the controlling owner (family firms and firms with an institutional investor) and the level of contestability by other shareholders. In order to test these hypotheses, the authors build an original database identifying, at a 10% threshold, the ultimate shareholders of a sample of 96 Spanish firms listed during 2008–2018 (1,002 obs).

The results show that there is no significant relationship between the ownership concentration and the R&D investment. Only when the authors consider the nature of the main shareholder, the authors find that in family firms there is an inverted U relationship between ownership and R&D, so that at low levels of ownership, the R&D increases, while at high levels of ownership (that we compute around 54%) the R&D decreases. Also, when the main shareholder is an institutional investor, the greater its ownership, the higher the R&D investment. Finally, the authors test that, contrary to what mainstream suggests, contestability in family firms is higher when ownership in the hands of other family shareholders increases.

The work uses an original database to test a nonlinear relationship between ownership and R&D investment in family firms. Also, the study addresses a topic hardly ever discussed in the literature about R&D as it is the role of the contestability by other controlling shareholders.

El objetivo del presente trabajo es analizar la relación existente entre la estructura de propiedad y la innovación corporativa para una muestra de empresas cotizadas españolas.

Utilizando los planteamientos de la teoría de la agencia y de la perspectiva de la riqueza socioemocional proponemos que la I+D empresarial está relacionada con la estructura de propiedad, específicamente con la naturaleza del accionista de control (empresas familiares y empresas con un inversor institucional como principal accionista) y con el grado de contestabilidad por parte de otros accionistas significativos. A fin de testar nuestras hipótesis, construimos ad hoc una base de datos de propiedad original en la que identificamos, al umbral del 10% de propiedad, a los accionistas últimos de una muestra de 96 empresas cotizadas españolas para el periodo 2008–2018 (1.002 obs).

Nuestros resultados muestran que no existe relación significativa entre la concentración de propiedad y la inversión en I + D. Solo cuando consideramos la naturaleza del principal accionista encontramos que en las empresas familiares la relación entre la propiedad de la familia y la innovación corporativa adopta una forma de U invertida, tal que a bajos niveles de propiedad la I + D crece, mientras que a altos niveles de propiedad (que computamos en torno al 54% de propiedad) la inversión en I + D decrece. Asimismo, en las empresas con un inversor institucional como principal accionista, cuanto mayor es la propiedad de este inversor institucional, mayor es la I + D de la empresa. Finalmente testamos que, en contra de la corriente dominante, en las empresas familiares la propiedad en manos de otras familias incrementa el grado de contestabilidad a la familia controladora respecto a su inversión en I + D.

El trabajo utiliza una base de datos de propiedad original para testar una relación no lineal entre concentración de propiedad e innovación corporativa en las empresas familiares. Asimismo, el estudio aborda un tema apenas analizado en la literatura de I + D como es el papel de la contestabilidad al accionista de control.