The politics and poetics of coexistence : experiments at the intersection of art and environmental engineering

This research project explores how interdisciplinary art practices can provide ways for questioning and envisaging alternative modes of coexistence between humans and the non-humans who together, make up the environment. As a practiceled project, it combines a body of creative work (50%) and this exegesis (50%). My interdisciplinary artistic practice appropriates methods and processes from science and engineering and merges them into artistic contexts for critical and poetic ends. By blending pseudo-scientific experimentation with creative strategies like visual fiction, humour, absurd public performance and scripted audience participation, my work engages with a range of debates around ecology. This exegesis details the interplay between critical theory relating to these debates, the work of other creative practitioners and my own evolving artistic practice. Through utilising methods and processes drawn from my prior career in water engineering, I present an interdisciplinary synthesis that seeks to promote improved understandings of the causes and consequences of our ecological actions and inactions.

Modelling the failure of thin layered mortar joints in masonry

This paper deals with the failure of high adhesive, low compressive strength, thin layered polymer mortar joints in masonry through a contact modelling in finite element framework. Failure due to combined shear, tensile and compressive stresses are considered through a constitutive damaging contact model that incorporates traction–separation as a function of displacement discontinuity. The modelling method is verified using single and multiple contact analyses of thin mortar layered masonry specimens under shear, tensile and compressive stresses and their combinations. Using this verified method, the failure of thin mortar layered masonry under a range of shear to tension ratios and shear to compression ratios has been examined. Finally, this model is applied to thin bed masonry wallettes for their behaviour under biaxial tension–tension and compression–tension loadings perpendicular and parallel to the bed joints.

Reducing the Risk of Alcohol and Other Drugs in Construction : An Australian Assessment

There is increasing concern about the impact of employees’ alcohol and other drug (AOD) consumption on workplace safety, particularly within the construction industry. No known study has scientifically evaluated the relationship between the use of drugs and alcohol and safety impacts in construction, and there has been only limited adoption of nationally coordinated strategies, supported by employers and employees to render it socially unacceptable to arrive at a construction workplace with impaired judgment from AODs. This research aims to scientifically evaluate the use of AODs within the Australian construction industry in order to reduce the potential resulting safety and performance impacts and engender a cultural change in the workforce. Using the Alcohol Use Disorders Identification Test (AUDIT), the study will adopt both quantitative and qualitative methods to evaluate the extent of general AOD use in the industry. Results indicate that a proportion of the construction sector may be at risk of hazardous alcohol consumption. A total of 286 respondents (58%) scored above the cut-off score for risky alcohol use with 43 respondents (15%) scoring in the significantly ‘at risk’ category. Other drug use was also identified as a major issue that must be addressed. Results support the need for evidence-based, preventative educational initiatives that are tailored specifically to the construction industry.

Improving the quality of fourth year civil engineering research projects through bibliographic instruction

Faculty and reference librarians at the Queensland University of Technology have collaborated in an attempt to improve the quality of literature reviews in civil engineering final -year research projects. This article describes the instructional program devised and the level of faculty support for the librarians' contribution, and presents survey results revealing how students could most benefit from BI and how the classroom collaboration affected student project work. The authors offer some observations about the possible impact of 81 in general, and on engineers in particular, which may provide a focus for future research.

In vitro biocompatibility of different polyester membranes

Nowadays, synthetic biodegradable polymers, such as aliphatic polyesters, are largely used in tissue engineering. They provide several advantages compared to natural materials which use is limited by immunocompatibility, graft availability, etc. In this work, poly(L-lactic) acid (PLLA), poly(DL-lactic) acid (PDLA), poly-epsilon-caprolactone (PCL), poly(L-lactic)-co-caprolactone (molar ratio 70/30) (PLCL) were selected because of their common use in tissue engineering. The membranes were elaborated by solvent casting. Membrane morphology was investigated by atomic force microscopy. The membranes were seeded with human fibroblasts from cell line CRL 2703 in order to evaluate the biocompatibility by the Alamar blue test. The roughness of the membranes ranged from 4 nm for PDLA to 120 nm and they presented very smooth surface except for PCL which beside a macroscopic structure due to its hydrophobicity. Human fibroblasts proliferated over 28 days on the membranes proving the non-in vitro toxicity of the materials and of the processing method. A further step will be the fabrication of three-dimensional scaffold for tissue engineering and the treatment of the scaffolds to augment cell adhesion.

Steady natural convection of non-Newtonian power-law fluid in a trapezoidal enclosure

Numerically investigation of free convection heat transfer in a differentially heated trapezoidal cavity filled with non-Newtonian Power-law fluid has been performed in this study. The left inclined surface is uniformly heated whereas the right inclined surface is maintained as uniformly cooled. The top and bottom surfaces are kept adiabatic with initially quiescent fluid inside the enclosure. Finite volume based commercial software FLUENT 14.5 is used to solve the governing equations. Dependency of various flow parameters of fluid flow and heat transfer is analyzed including Rayleigh number, Ra ranging from 10^5 to 10^7, Prandtl number, Pr of 100 to 10,000 and power index, n of 0.6 to 1.4. Outcomes have been reported in terms of isotherms, streamline, and local Nusselt number for various Ra, Pr, n and inclined angles. Grid sensitivity analysis is performed and numerically obtained results have been compared with those results available in the literature and found good agreement.

Reconstructing places and spaces in blended work integrated learning

This paper considers the emergence and ongoing development of an embedded, studentnegotiated work placement model of Work Integrated Learning (WIL) in the engineering and built environment disciplines at an Australian metropolitan university. The characteristics of the model and a continuous improvement strategy are provided. The model is characterised by large student cohorts independently sourcing and negotiating relevant work placements and completing at least one, mandatory credit-bearing WIL unit. Through ongoing analyses and evaluation of the model more experiential and collaborative learning approaches have been adopted. This has included the creation of blended learning spaces using technology. The paper focuses on the five year journey travelled by the teaching team as they embarked on ways to improve curriculum, pedagogy, administrative processes and assessment - effectively relocating much of their interaction with students online. The insights derived from this rich, single case study should be of interest to others considering alternative ways of responding to increasing student enrolments in WIL and the impact of blended learning in this context.

Injury severity of pedestrian crashes in Singapore

Singapore is a highly urbanized city-state country where walking is an important mode of travel. Pedestrians form about 25% of road fatalities every year, making them one of the most vulnerable road user groups in Singapore. Engineering measures like provision of overhead pedestrian crossings and raised zebra crossings tend to address pedestrian safety in general, but there may be occasions where pedestrians are particularly vulnerable so that targeted interventions are more appropriate. The objective of this study is to identify factors and situations that affect the injury severity of pedestrians involved in traffic crashes. Six years of crash data from 2003 to 2008 containing around four thousands pedestrian crashes at roadway segments were analyzed. Injury severity of pedestrians—recorded as slight injury, major injury and fatal—were modeled as a function of roadway characteristics, traffic features, environmental factors and pedestrian demographics by an ordered probit model. Results suggest that the injury severity of pedestrians involved in crashes during night time is higher indicating that pedestrian visibility during night is a key issue in pedestrian safety. The likelihood of fatal or serious injuries is higher for crashes on roads with high speed limit, center and median lane of multi-lane roads, school zones, roads with two-way divided traffic type, and when pedestrians cross the roads. Elderly pedestrians appear to be involved in fatal and serious injury crashes more when they attempt to cross the road without using nearby crossing facilities. Specific countermeasures are recommended based on the findings of this study.

Comparative study of failure mechanisms in steel and concrete members strengthened with CFRP composites

Over the last decade advanced composite materials, like carbon fibre reinforced polymer (CFRP), have increasingly been used in civil engineering infrastructure. The benefits of advanced composites are rapidly becoming evident. This paper focuses on the comparative performance of steel and concrete members retrofitted by carbon fibre reinforced polymers. The objective of this work is a systematic assessment and evaluation of the performance of CFRP for both the concrete and steel members available in the technical literature. Existing empirical and analytical models were studied. Comparison is made with respect to failure mode, bond characteristics, fatigue behaviour, durability, corrosion, load carrying capacity and force transfer. It is concluded that empirical expressions for the concrete-CFRP composite are not readily suited for direct use in the steel-CFRP composite. This paper identifies some of the major issues that need further investigation.

Relationship between head contractors and subcontractors in the construction industry : a critical review

The interaction between head contractor and subcontractor in modern construction often contributes to the degree of success or failure of any large-scale construction project. In this paper, previous research on the relationship and interaction between head contractor and subcontractor is examined in order to establish how these relationships will affect the overall performance of a project. Based on the review, research questions on how to best manage the interaction and relationship between these two vital project participants are proposed and future research direction discussed.

Structural dynamics education in the new millennium

Structural Dynamics is the study of the response of structures to dynamic or time varying loads. This topic has emerged to be one of importance to all structural engineers due to three important issues with structural engineering in the new millennium. These are: (1) vibration and problems in slender structures that have emerged due to new material technology and aesthetic requirements, (ii) ageing structures such as bridges whoese health needs to be monitored and appropriate retrofitting carried out to prevent failure and (iii) increased vulnerability of structures to random loads such as seismic, impact and blast loads. Knowledge of structural dynamics is necessary to address these issues and their consequences. During the past two decades, research in structural dynamics has generated considerable amount of new information to address these issues. This new knowledge is not readily made available to practicing engineers and very little or none of it enters the classrooms. There is no universal emphasis on including structural dynamics and their recently generated new knowledge into the civil/structural curriculum. This paper argues for the need to include structural dynamics into the syllabus of all civil engineering courses especially those having a first or second major in structural engineering. This will enable our future structural engineers to design and maintain safe and efficient structures.

Small RNA viruses of insects : expression in plants and RNA silencing

Interest in insect small RNA viruses (SRVs) has grown slowly but steadily. A number of new viruses have been analyzed at the sequence level, adding to our knowledge of their diversity at the level of both individual virus species and families. In particular, a number of possible new virus families have emerged. This research has largely been driven by interest in their potential for pest control, as well as in their importance as the causal agents of disease in beneficial arthropods. At the same time, research into known viruses has made valuable contributions to our understanding of an emerging new field of central importance to molecular biology-the existence of RNA-based gene silencing, developmental control, and adaptive immune systems in eukaryotes. Subject to RNA-based adaptive immune responses in their hosts, viruses have evolved a variety of genes encoding proteins capable of suppressing the immune response. Such genes were first identified in plant viruses, but the first examples known from animal viruses were identified in insect RNA viruses. This chapter will address the diversity of insect SRVs, and attempts to harness their simplicity in the engineering of transgenic plants expressing viruses for resistance to insect pests. We also describe RNA interference and antiviral pathways identified in plants and animals, how they have led viruses to evolve genes capable of suppressing such adaptive immunity, and the problems presented by these pathways for the strategy of expressing viruses in transgenic plants. Approaches for countering these problems are also discussed. © 2006 Elsevier Inc. All rights reserved.

Time as the critical factor in the investigation of the relationship between pollutant wash-off and rainfall characteristics

The approach adopted for investigating the relationship between rainfall characteristics and pollutant wash-off process is commonly based on the use of parameters which represent the entire rainfall event. This does not permit the investigation of the influence of rainfall characteristics on different sectors of the wash-off process such as first flush where there is a high pollutant wash-off load at the initial stage of the runoff event. This research study analysed the influence of rainfall characteristics on the pollutant wash-off process using two sets of innovative parameters by partitioning wash-off and rainfall characteristics. It was found that the initial 10% of the wash-off process is closely linked to runoff volume related rainfall parameters including rainfall depth and rainfall duration while the remaining part of the wash-off process is primarily influenced by kinetic energy related rainfall parameters, namely, rainfall intensity. These outcomes prove that different sectors of the wash-off process are influenced by different segments of a rainfall event.

Considering a whole-of-community approach to integrating nature in cities, an international case study of Vauban, Germany

Globally, cities face a convergence of complex and rapidly evolving challenges, including climate change, resource shortages, population growth and urbanization, and financial pressures. Biophilic urbanism is an emerging design principle capable of considering the multidimensional and interdependent complexities of urban systems and infrastructure, which through the use of natural design features, can meet society’s inherent need for contact with nature, and assist efforts to respond to these growing challenges. Considering the imperative for addressing these challenges, this paper proposes that significant lessons can be learned from existing examples of biophilic urbanism, avoiding ‘re-invention of the wheel’ and facilitating accelerated innovation in other areas. Vauban is a 38-hectare brownfield development located 3 kilometers from the centre of Germany’s ‘ecological capital’ of Freiburg city. It was developed using an innovative process with strong community participation and reinterpreted developer roles to produce an example of integrated sustainability. Innovation in transport, energy, housing, development and water treatment has enabled a relatively high-density, mixed-use development that integrates a considerable amount of nature. This paper discusses Vauban in light of research undertaken over the last two years through the Sustainable Built Environment National Research Centre in Australia, to investigate emerging elements of ‘biophilic urbanism’ (nature-loving cities), and their potential to be mainstreamed within urban environments. The paper considers the interplay between the policies, community dynamics and innovations in Vauban, within the context of the culture, history and practice of sustainability in Germany, and how these have enabled nature to be integrated into the urban environment of Vauban while achieving other desirable goals for urban areas. It highlights potential applications from Vauban for Australian cities.

Hybrid genetic algorithm for elimination of severe stress concentration in railhead ends

This paper presents a computational method for eliminating severe stress concentration at the unsupported railhead ends in rail joints through innovative shape optimization of the contact zone, which is complex due to near field nonlinear contact. With a view to minimizing the computational efforts, hybrid genetic algorithm method coupled with parametric finite element has been developed and compared with the traditional genetic algorithm (GA). The shape of railhead top surface where the wheel contacts nonlinearly was optimized using the hybridized GA method. Comparative study of the optimal result and the search efficiency between the traditional and hybrid GA methods has shown that the hybridized GA provides the optimal shape in fewer computational cycles without losing accuracy. The method will be beneficial to solving complex engineering problems involving contact nonlinearity.