1,893 research outputs found
Transparent Dynamic reconfiguration for CORBA
Distributed systems with high availability requirements have to support some form of dynamic reconfiguration. This means that they must provide the ability to be maintained or upgraded without being taken off-line. Building a distributed system that allows dynamic reconfiguration is very intrusive to the overall design of the system, and generally requires special skills from both the client and server side application developers. There is an opportunity to provide support for dynamic reconfiguration at the object middleware level of distributed systems, and create a dynamic reconfiguration transparency to application developers. We propose a Dynamic Reconfiguration Service for CORBA that allows the reconfiguration of a running system with maximum transparency for both client and server side developers. We describe the architecture, a prototype implementation, and some preliminary test result
On the Notion of Abstract Platform in MDA Development
Although platform-independence is a central property in MDA models, the study of platform-independence has been largely overlooked in MDA. As a consequence, there is a lack of guidelines to select abstraction criteria and modelling concepts for platform-independent design. In addition, there is little methodological support to distinguish between platform-independent and platform-specific concerns, which could be detrimental to the beneficial exploitation of the PIM-PSM separation-of-concerns adopted by MDA. This work is an attempt towards clarifying the notion of platform-independent modelling in MDA development. We argue that each level of platform-independence must be accompanied by the identification of an abstract platform. An abstract platform is determined by the platform characteristics that are relevant for applications at a certain level of platform-independence, and must be established by balancing various design goals. We present some methodological principles for abstract platform design, which forms a basis for defining requirements for design languages intended to support platform-independent design. Since our methodological framework is based on the notion of abstract platform, we pay particular attention to the definition of abstract platforms and the language requirements to specify abstract platforms. We discuss how the concept of abstract platform relates to UML
Different perspectives on management systems integration
Increasingly competitive economies and the market globalisation process have led
many organisations to implement management systems as a differential against
competition. However, with the variety of standards available, they felt the need to
integrate management subsystems aiming at resources and skills optimisation, in
order to achieve performance maximisation of the resulting integrated management
system (IMS). Added to this, it is known that the value of a single certificate is
inversely proportional to the overall increase in certificate numbers. This paper
intends to report the study results focusing on critical success factors (CSFs)
assessment, difficulties faced by organisations when implementing an IMS, and the
resulting benefits. Additionally, the quantitative evolution of IMS in Portuguese
companies until 2011 is reported, showing how IMS typologies evolved and
increased their relative ‘weight’ among Portuguese certified companies. Related to
the study, the sample was composed of four Portuguese IMS ruled organisations
based on quality, environment and occupational health and safety certified
management subsystems. The data collection methodology was based on semistructured
interviews with the management system manager, through which it was
sought to analyse the entire integration process. Results suggest that management
subsystems integration contributes positively to the studied organisations. Top
management involvement, human and financial resources availability and training
were identified as subsystems integration CSF. Among the difficulties faced by
organisations they pointed out the non existence of a previous organisational
structure and the employees’ behaviour changes
Integrated management systems – quality, environment and health and safety: motivations, benefits, difficulties and critical success factors
Following the process of economic globalization and increasingly competitive markets, many organizations have
implemented wider management systems, as distinctive factor against competition. However, with the increasing
standards organizations found themselves needing to integrate management systems aiming the expertise and resources
optimization. As a result of that integration a maximum performance of the management system can be achieved. It was
defined as this study aim the assessment of critical success factors for implementing an integrated management system,
and what were the difficulties felt by organizations during the integration process. The type of sampling was nonprobabilistic
by convenience. The sample was composed with four organizations with certified management system of
quality, environment and occupational health and safety. The type of study was descriptive and exploratory level I. To
collect data semi-structured interviews were conducted with management system managers, where the entire integration
process was examined. It can be concluded that the integrated management system contributes positively to the studied
organizations, leading to benefits at the organizational processes, cost reduction, efficiency gains, among others. It can
also be concluded that the involvement of top management, the existence of human and financial resources, training, as
well as the employee motivation involvement, clear goals and meeting deadlines, are factors that can lead to successful
systems integration. The change on both organization structure and behavior of employees was the most outline difficulty
felted by organizations
Sistemas integrados de gestão: factores críticos de sucesso
Face ao processo de globalização das economias
e mercados cada vez mais competitivos,
muitas organizações implementaram
sistemas de gestão mais abrangentes
como diferencial diante da concorrência.
No entanto, com o aumento de referenciais,
viram-se na necessidade de integrar os
sistemas de gestão tendo por objectivo a
optimização de recursos e de competências,
com vista a alcançar a maximiza-
ção do desempenho do sistema de gestão
resultante. Neste sentido, definiram-se
como objectivos do estudo avaliar quais
os factores críticos de sucesso para a implementação
de um sistema integrado de
gestão e quais as dificuldades encontradas
pelas organizações aquando da integração
dos sistemas de gestão. A amostragem
foi do tipo não probabilística e quanto
à técnica, a mesma foi por conveniência.
A amostra foi composta por quatro organizações
com sistemas de gestão da qualidade,
ambiente e segurança e saúde do
trabalho certificad
Seller-buyer supply chain: a game theory framework
We present a game theoretical framework to study competition and collaboration scenarios in seller-buyer supply chains, representing a manufacturer that wholesales a product to a retailer who, in turn, retails to the final consumer. We study cooperative and non-cooperative scenarios, by considering in the first case a Stackelberg game under both the situations where one of the players, either the buyer or the seller, plays the leading role by taking the initiative and forcing the strategy of the other player, the follower. In the cooperative game, we analyse scenarios where the pro t of both players are increased when applying joint cooperative strategies. We also compute the Nash equilibria. This is undergoing work.info:eu-repo/semantics/publishedVersio
Dimensionamento de estruturas de transição
A transfer structure is a structure that alters the load path of the
gravity loads, shifting the line of thrust laterally to a different
vertical alignment. Transfer structures are introduced in buildings
that feature discontinuities in vertical elements and where a direct
load path to the foundations is not possible. This paper presents
an overview of existing transfer systems and provides guidance
on their design and construction. Extensive research on buildings
with transfer structures was carried out with the aim of developing
a rational typology of these structures. The results can be broken
down into five main types: BEAM, TRUSS, INCLINED STRUT, PLATE,
and ARC H & CABLE. In addition, transfer structures’ design is often
outside the scope of normal code guidance and may require a degree
of engineering judgment. This paper also highlights the key aspects
that determine the structural design of transfer structures, as well as
typical construction methods.Uma estrutura de transição (ET) é uma estrutura que altera o
caminho-de-carga das forças gravíticas. ETs são inseridas em edifícios
que exibem descontinuidades em pilares ou paredes resistentes, e
onde um caminho-de-carga direto para as fundações não é possível.
Estas estruturas constituem elementos condicionantes do edifício
onde se inserem, e o seu impacto no custo e no tempo de construção
pode ser significativo. Este documento apresenta uma perspetiva
geral das estruturas de transição existentes em edifícios e reúne
princípios orientadores para o seu dimensionamento e construção.
Foi realizada uma extensa pesquisa sobre edifícios com ETs em todo
o mundo com o objetivo de desenvolver uma tipificação adequada
destas estruturas. O resultado consiste em cinco tipos principais:
Viga, Treliça, Escora inclinada, Placa e Arco & Cabo.info:eu-repo/semantics/publishedVersio
A framework for modular and customizable software analysis
This paper presents a framework for the analysis of software artifacts. We revise and propose techniques that aid in the manipulation and combination of target-language specific tools, and in handling and controlling the results of such tools. We also propose to integrate under our framework techniques that are capable of performing language independent analyses.
The final result of our work is an analysis environment that is modular and flexible and that allows easy and elegant implementations of complex analysis suites.
We finally conduct a proof of concept for our framework by analyzing a well-known, widely used open-source software package.This work is partly funded by ERDF - European Regional Development Fund through the COMPETE Programme (operational programme for competitiveness) and by National Funds through the FCT - Fundacao para a Ciencia e a Tecnologia (Portuguese Foundation for Science and Technology) within projects FCOMP-01-0124-FEDER-010049, and FCOMP-01-0124-FEDER-022701
Bond-slip effect in the assessment of RC structures subjected to seismic actions
The effect of bond-slip in the assessment of reinforced concrete structures under static or dynamic cyclic loads with numerical
models may be significant. Its relevance is discussed in this paper, by analysis of the correlation of experimental and analytical
results. The latter were obtained with a perfect bond-based model and with a fiber-section beam-column model which makes
it possible to consider the effect of bond-slip in the vicinity of exterior as well of interior joints of reinforced concrete frame
structures. The experimental results consist of a shaking table test of a reinforced concrete frame, with predominant flexural
condition, in agreement with the premisses of this research. The model with bond-slip was capable of predicting the structural
behaviour in a very satisfactory manner. Furthermore, the results of the assessment including bond-slip are significantly more
accurate than those assuming perfect bond.info:eu-repo/semantics/publishedVersio
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