NHL 3.5 mortars with scrap tire rubber

The use of wastes and industrial by-products as building materials is an important issue in order to decrease costs with waste management and the embodied energy of building products. Scrap tire rubber has been studied as aggregate for cementitious materials. Natural hydraulic limes are natural binders with particular characteristics of both air and hydraulic binders. Their specifications became stricter with the last version of EN 459-1:2010. In this study scrap tire rubber was used as additional aggregate of mortars, based on NHL3.5 and natural sand. Different particle size fractions and proportions of scrap tire rubber were used: a mix obtained almost directly from industry (only after sieving for preparation of particle sizes similar to mortar aggregate) and separated fine, medium and coarse fractions; 0%, 18%, 36% and 54% weight of binder, corresponding to 2.5%, 5% and 7.5% weight of sand. The influence of the rubbers´ additions on the mortars´ fresh state, mechanical and physical performance is presented, namely by flow table consistency, water retention, fresh bulk density, dynamic elasticity modulus, flexural and compressive strength, open porosity and bulk density, capillary absorption, drying and thermal conductivity. The use of the rubber mix coming from the waste tire industry seems advantageous and may open possibilities for use as raw material by the mortars industry

СУХИЕ СТРОИТЕЛЬНЫЕ СМЕСИ НА ОСНОВЕ ПРИРОДНОЙ ГИДРАВЛИЧЕСКОЙ ИЗВЕСТИ (NHL 3.5) С ДОБАВКОЙ РЕЗИНОВОЙ КРОШКИ, ПОЛУЧЕННОЙ ИЗ ОТРАБОТАННЫХ ПОКРЫШЕК (in Russian)

The use of wastes and industrial by-products as building materials is an important issue in order to decrease costs with waste management and the embodied energy of building products. In this study scrap tire rubber was used as additional aggregate of mortars based on natural hydraulic lime NHL 3.5 and natural sand. Different particle size fractions and proportions of scrap tire rubber were used: a mix obtained directly from industry and separated fine, medium and coarse fractions; 0 %, 18 %, 36 % and 54 % of the weight of binder, corresponding to 2.5 %, 5 % and 7.5 % of the weight of sand. As mortars based on NHL specifications became stricter with the current version of EN 459–1:2015, the influence of the rubber’s additions on the mortars’ fresh state, mechanical and physical performance is presented in this work: flow table consistency, water retention, dynamic elasticity modulus, flexural and compressive strength, open porosity and bulk density, capillary absorption, drying and thermal conductivity are studied. The use of the rubber mix coming from the waste tire industry seems advantageous and may open possibilities for use as raw material by the mortars industry.Secil Argamassa

ICT Diffusion, inward foreign direct investment,and entrepreneurship in developing countries:a research note

The last decades have stablished the fundamental importance of technological progress for economic growth and wealth creation. Most new technology is created in developed countries. For these countries, the fundamental problem for growth is to harness the economic value of new inventions by converting them into new products, processes and organizational means. Entrepreneurship plays a fundamental role in this course of events (Shane 2001; Michelacci 2003; Acs et al. 2004; 2009). In developing countries the diffusion of new technologies plays an essential role in fostering growth

O Reequipamento da Indústria de Defesa. Subsídios para uma Política de Armamento

Este trabalho começa por notar que, não obstante a problemática do reequipamento das Forças Armadas (FA) vir a merecer o interesse expresso de sucessivos Governos, o facto é que as FA consideram que o seu equipamento continua a apresentar graves deficiências. Por outro lado, admitindo que é do interesse estratégico nacional a manutenção de uma expressão mínima suficiente de uma “indústria de defesa”, na sequência e em cumprimento dos objectivos programáticos também estabelecidos por sucessivos Governos, é necessário e urgente definir uma política para a reestruturação deste sector. Aborda-se depois a questão do âmbito da política a definir para concluir pela conveniência englobar ambas as vertentes, ou seja: “É necessário e urgente definir uma “Política de Armamento” que aponte os objectivos e as vias institucionais que norteiem, enquadrem e apoiem o reequipamento das Forças Armadas e, simultânea e conjugadamente, concorram para a reestruturação e desenvolvimento da Indústria de Defesa” Depois de analisar a situação e as implicações da envolvente externa e do quadro nacional, conclui-se o trabalho com a apresentação de “linhas gerais de acção”, como contributo para a definição da Política de Armamento

Speciation in marine environments: Diving under the surface

Marine environments are inhabited by a broad representation of the tree of life, yet our understanding of speciation in marine ecosystems is extremely limited compared with terrestrial and freshwater environments. Developing a more comprehensive picture of speciation in marine environments requires that we 'dive under the surface' by studying a wider range of taxa and ecosystems is necessary for a more comprehensive picture of speciation. Although studying marine evolutionary processes is often challenging, recent technological advances in different fields, from maritime engineering to genomics, are making it increasingly possible to study speciation of marine life forms across diverse ecosystems and taxa. Motivated by recent research in the field, including the 14 contributions in this issue, we highlight and discuss six axes of research that we think will deepen our understanding of speciation in the marine realm: (a) study a broader range of marine environments and organisms; (b) identify the reproductive barriers driving speciation between marine taxa; (c) understand the role of different genomic architectures underlying reproductive isolation; (d) infer the evolutionary history of divergence using model‐based approaches; (e) study patterns of hybridization and introgression between marine taxa; and (f) implement highly interdisciplinary, collaborative research programmes. In outlining these goals, we hope to inspire researchers to continue filling this critical knowledge gap surrounding the origins of marine biodiversity

Modeling material failure in concrete structures under cyclic actions

A constitutive model devised for the analysis of concrete structures, and suitable for generic two- or three-dimensional applications, is presented and validated. For plain concrete a tension-compression distinguishing stress split is performed, and two scalar damage variables account for the degradation induced by the tensile and compressive stress components. As outcomes the model reproduces the stiffness recovery upon load reversal, and it captures the strength enhancement under multiaxial compression. Besides, the simple formulation as well as the extremely reduced number of parameters involved in the concrete model makes it quite suitable for the analysis of real structures, and constitutes a useful design tool. As regards to the nonlinear performance of the steel reinforcement, the explicit Giuffrè–Menegotto–Pinto model is adopted. Efficiency of the global model is illustrated via two seismic applications: one concerning an arch dam, and the other a six-floor reinforced concrete wall. The latter application is presented for validation purposes

Interpreting the Solution Architect’s Role at a leading IT and Consultancy Company

At the end of the twentieth century, an individual or a small company could design and develop an application or even some bigger and scalable systems. However, due to their increasing complexity, project size and required higher levels of integration, the need for new roles and processes associated with software development drastically increased, calling for skills to assure the integrity and effectiveness of solutions. A new role, called “Solution Architect”, emerged over time and has been formally used in leading companies such as Cisco, IBM, Microsoft, Oracle and SAP, but it is still lacking agreement on its scope and responsibilities. Having the retail sector as the context in which a leading IT and consultancy company operates, this research builds upon the experience of seven Solution Architects from a pool of fourteen inquiring them on their perceptions about their roles in order to better understand the required skills and boundaries of this new role against more established architectural roles. At the end of this research, it was clear that the interpretations of this role’s span across a project’s lifecycle as well as the boundaries to other roles such as the Enterprise Architect’s one were not the same. Nevertheless, the consultancy side of the Solution Architect role gathered the most consensuses as opposed to the more traditional technical side, which wasn’t selected by any Solution Architect. Anyway, the scope dilemma still persists within a project leading to a role overlap between Enterprise and Solution Architect.This work is supported by FEDER funding through the Competitiveness Factors Operational Programme - COMPETE and national funding through FCT - Foundation for Science and Technology under the project FCOMP-01-0124-FEDER-022674

RODA - A Service-Oriented Repository to Preserve Authentic Digital Objects

4th International Conference on Open RepositoriesThis presentation was part of the session : Fedora User Group PresentationsDate: 2009-05-20 03:30 PM – 05:00 PMIn mid 2006, the Portuguese National Archives (Directorate-General of the Portuguese Archives) launched a project called RODA (Repository of Authentic Digital Objects) aiming at identifying and bringing together all the necessary technology, human resources and political support to carry out long-term preservation of digital materials being produced by the Portuguese public administration. As part of the original goals of RODA was the development of a digital repository capable of ingesting, managing and providing access to the various types of digital objects produced by national public institutions. The development of such repository should be supported by open-source technologies and, as much as possible, be based on existing standards. Since RODA is nearly finished, this communication aims at describing its main results.European Union; POAP; Ministry of Culture; Portuguese Republi