Critical infrastructure systems : security analysis and modelling approach

A system security analysis and system modelling framework tool is proposed adopting an associated conceptual methodology as the basis for assessing security and conceptually modelling a critical infrastructure system incident. The intent is to identify potential system security issues and gain operational insights that will contribute to improving system resilience, contingency planning, disaster recovery and ameliorating incident management responses for critical infrastructure system incidents. The aforementioned system security analysis and modelling framework is applied to an adverse critical infrastructure system incident case study. This paper reports on the practical application of the framework to a case study of an actual critical infrastructure system failure and the resultant incident implications for the system and the wider regional communities.

Underpricing of infrastructure of IPOs: evidence from India

This paper explores the underpricing of initial public offerings (IPOs) made by infrastructure companies in India from 2004 to 2010, and follows Dimovski who reported that in the Australian market, infrastructure IPOs did not produce underpricing returns that were statistically significantly different to zero. The objective of this paper is to investigate the underpricing of infrastructure IPOs in the emerging market of India and to explore factors that may influence the underpricing of infrastructure IPOs in India. The results show that, on average, the underpricing returns were 25.4% and statistically significantly different to zero, while money left on the table, in aggregate is not. In contrast to Australian evidence, significant underpricing in Indian infrastructure IPOs indicates greater risk of these investments. We find that oversubscription, government ownership and issue size are significant variables in explaining underpricing in Indian infrastructure IPOs.

Identifying attributes contributing to environmental sustainability of public-private partnership infrastructure projects

Due to increasing demands for new infrastructure and an aim to reduce initial public investment, Australian government agencies are increasingly using public-private partnerships (PPPs) as a form of delivery for infrastructure projects. Environmentally, there is growing pressure for the building industry in general to become more sustainable. Moreover, as the built environment continues to grow each year, the performance of buildings as a whole will need to continually improve purely for national energy consumption to remain stable. Based on a systematic and extensive review on relevant literature, this paper has identified the key attributes that will influence the environmental sustainability of infrastructure completed through a PPP. The key attributes are grouped into five groups defined by whom or what has the majority of control over the attribute. Meanwhile, the key attributes are explored and their influence on environmental sustainability justified. This paper was able to not only identify significant factors involved in creating environmental sustainability in infrastructure PPPs, but also trends of the key attributes. It has been found that (1) the longevity of the contract in a PPP project allows greater innovation into environmental sustainability than traditional methods of procurement, (2) innovation is a requirement for the improving upon environmental performance in the built environment, (3) improvements to environmental sustainability relies upon a positive relationship between economic and environmental benefits, and (4) the key attributes for PPP projects are decided upon relatively early in the contract. Due to space limit, detailed discussion on each of the identified attributes is not provided in this paper. Nonetheless, further research direction is discussed.

Who uses new walking and cycling infrastructure and how? Longitudinal results from the UK iConnect study

Objective
To examine how adults use new local walking and cycling routes, and what characteristics predict use.

Methods
1849 adults completed questionnaires in 2010 and 2011, before and after the construction of walking and cycling infrastructure in three UK municipalities. 1510 adults completed questionnaires in 2010 and 2012. The 2010 questionnaire measured baseline characteristics; the follow-up questionnaires captured infrastructure use.

Results
32% of participants reported using the new infrastructure in 2011, and 38% in 2012. Walking for recreation was by far the most common use. In both follow-up waves, use was independently predicted by higher baseline walking and cycling (e.g. 2012 adjusted rate ratio 2.09 (95% CI 1.55, 2.81) for > 450 min/week vs. none). Moreover, there was strong specificity by mode and purpose, e.g. baseline walking for recreation specifically predicted walking for recreation on the infrastructure. Other independent predictors included living near the infrastructure, better general health and higher education or income.

Conclusions
The new infrastructure was well-used by local adults, and this was sustained over two years. Thus far, however, the infrastructure may primarily have attracted existing walkers and cyclists, and may have catered more to the socio-economically advantaged. This may limit its impacts on population health and health equity.

Engineering a distributed infrastructure for large-scale cost-effective content dissemination over urban vehicular networks

This paper proposes a practical and cost-effective approach to construct a fully distributed roadside communication infrastructure to facilitate the localized content dissemination to vehicles in the urban area. The proposed infrastructure is composed of distributed lightweight low-cost devices called roadside buffers (RSBs), where each RSB has the limited buffer storage and is able to transmit wirelessly the cached contents to fast-moving vehicles. To enable the distributed RSBs working toward the global optimal performance (e.g., minimal average file download delays), we propose a fully distributed algorithm to determine optimally the content replication strategy at RSBs. Specifically, we first develop a generic analytical model to evaluate the download delay of files, given the probability density of file distribution at RSBs. Then, we formulate the RSB content replication process as an optimization problem and devise a fully distributed content replication scheme accordingly to enable vehicles to recommend intelligently the desirable content files to RSBs. The proposed infrastructure is designed to optimize the global network utility, which accounts for the integrated download experience of users and the download demands of files. Using extensive simulations, we validate the effectiveness of the proposed infrastructure and show that the proposed distributed protocol can approach to the optimal performance and can significantly outperform the traditional heuristics.