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1.
In this paper we address the problem of information overload in synchronous group work: the large quantity of information, multiple information sources, and the need to sustain reciprocal interdependence have a negative impact on the capacity to attend to the group. We propose a group attention model characterizing the dynamic coupling between the group members and the mediating technology. Based on that model, we developed a compensation mechanism capable to estimate the most adequate time to raise the users?? attention to the group. We describe how this compensation mechanism was applied to synchronous brainstorming and present results from a laboratory experiment. The obtained results indicate that groups using the compensation mechanism produced 9.6% more ideas when compared to the control groups. A detailed post-hoc analysis of the data obtained in the experiment also indicates that users using the compensation mechanism had 7.5 s of extra uninterrupted time to think about and type an idea, which they began to write 6.4 s sooner, and completed in 4.2 s less time.  相似文献   
2.
A number of transportation infrastructure projects were conducted in Europe during the 1990s with the explicit objective of promoting regional cohesion goals through the improvement of the accessibility of peripheral regions. Given its peripheral situation in the Union, Portugal was a key target for some of these projects. A decade later, it is pertinent to ask whether the new infrastructure achieved its objective of promoting lagging regions. The objective of this paper is to analyze one of the lagging regions in Portugal, to try to establish the link between changes in accessibility levels brought by improvements in the transportation network, and two indicators commonly used in accessibility research (population and purchasing power), while controlling other variables of possible relevance, such as the levels of educational achievement of the population in the region. The analysis is based on the use of spatially autoregressive models which allow the representation of accessibility as spatially lagged variables of first and second order. The results place the contribution of accessibility changes in context, and point at the relevance of education as an alternative policy.  相似文献   
3.
In this paper, we present an optimization approach to depot location in one-way carsharing systems where vehicle stock imbalance issues are addressed under three trip selection schemes. The approach is based on mixed-integer programming models whose objective is to maximize the profits of a carsharing organization considering all the revenues and costs involved. The practical usefulness of the approach is illustrated with a case study involving the municipality of Lisbon, Portugal. The results we have obtained from this study provided a clear insight into the impact of depot location and trip selection schemes on the profitability of such systems.  相似文献   
4.
Biodiversity loss is a serious and ongoing global environmental problem. Economic instruments in biodiversity policies can contribute towards reconciling the conservation costs encountered at local level with the benefits of biodiversity conservation at higher levels of governance, from regional and national levels up to the global level. This paper outlines the theoretical foundations of fiscal transfers in conservation policies and also offers a concise account of existing international experience and future prospects. The recently amended Portuguese Local Finances Law (LFL) of 2007, with its groundbreaking new article on the promotion of local sustainability, is analysed in terms of the significance of fiscal transfers for municipal budgets. It is compared with its predecessor law, highlighting changes in fiscal revenues for selected municipalities in the country in relation to their designated conservation areas. The analysis shows that these ecological fiscal transfers can be significant for those municipalities with a large proportion of land under protected status. However, because it also introduces a considerable number of changes to the Portuguese fiscal transfer scheme, the ecological impact of the new LFL is difficult to grasp due to the presence of several crossover effects. The results obtained offer significant insights both for improving the Portuguese LFL and for designing new ecological fiscal transfer schemes.  相似文献   
5.
Collaborative spatial decision making (CSDM) involves multiple stakeholders making strategic decisions based on spatial data. Current CSDM tools have been exploring different ways to integrate spatial data with collaboration, distribution and mobility. Notably, decision-making support has not seen the same level of attention. This paper discusses the challenges raised by the integration of decision-making models in CSDM tools. We review a large collection of decision-making models using three different views: sequential, dynamic and continuous. From this review we derive a conceptual model and a set of functional requirements necessary to integrate decision-making support in CSDM tools. The conceptual model highlights the importance of several functions in decision-making processes: representing problems, finding alternatives and making choices (sequential view); classification and communication (dynamic view); and perception, comprehension and projection (continuous view). The paper also describes a prototype developed to validate the model. The paper provides two main research contributions: a unified view of decision-making support and an innovative CSDM tool blending spatial data with decision-making support.  相似文献   
6.
Human–computer interaction (HCI) design generally involves collaboration from professionals in different disciplines. Trained in different design education systems, these professionals can have different conceptual understandings about design. Recognizing and identifying these differences are key issues for establishing shared design practices within the educational community. Contributing to this understanding, we examined whether and how two different populations of students have different knowledge structures with respect to HCI design. We adopted the romantic, conservative and pragmatic dimensions, previously investigated in the related research, to elucidate those differences. This paper compares one specific type of design artefact—conceptual frameworks—created by groups of students with different educational backgrounds: Arts and Engineering. It was based on a set of 22 criteria divided by two main domains: scheme (addressing form) and realm (focusing on contents). The obtained results show that students with background in Engineering (1) focus more on the product of design; (2) rely less on conceptual frameworks to guide the design process; and (3) produce artefacts that are more constrained in terms of signal-to-noise ratio, definition of a symbolic system, and information organization and shaping. We suggest that conceptual frameworks serve to communicate and understand design practice. We note that Engineering students seem to be more susceptible to fixation than Arts students and suggest that an emphasis of reflection-in-action could help compensating this problem.  相似文献   
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Since their accession to the European Union in 1986, both Portugal and Spain have benefited from strong financial support. Both countries have experienced considerable growth in income per capita, converging towards average European levels. However, several studies suggest a high degree of persistence of regional asymmetries within the countries. This paper empirically analyses convergence among NUTS 3 regions of the Iberian Peninsula between 1995 and 2008. The results reveal divergent national trends and indicate no evidence of catching-up effects among the poorest regions, confirming the existence of economic clusters.  相似文献   
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A general equilibrium model with heterogeneous agents (with respect to wealth and ability) shows that differences across countries in intermediation costs and enforcement generate differences in occupational choice, firm size, credit, output and income inequality. Counterfactual experiments are performed for Latin American, European, transition and high growth Asian countries, with empirical estimates of each country's financial frictions and United States values for all other parameters. The results isolate the quantitative effect of these financial frictions in explaining the performance gap between each country and the United States, and depend critically on whether a general equilibrium factor price effect is operative.  相似文献   
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