How can rapid product development support sustainable product design research?

The consequences of the continually increasing impact of human development are confronting many people on a daily basis. Now more than ever there is a need to confront and challenge the way we live, one that is currently based around unsustainable production and consumption. Consequently, the design community has responded by recognising the potential opportunities associated with supporting sustainability, and well-informed designers are in a powerful position to help address some of the issues facing us. For many designers, reframing their practices and processes presents a great challenge. For new product designers to enter and engage in this new design era requires that sustainable design is deeply embedded into the curriculum of product design programmes. While many design programmes have embraced principle of sustainability, many have developed projects around the need for social responsibility, and have orientated teaching and studio projects around designing products to help those communities in greater need. Alongside is a rise in the number of sustainable design frameworks, all of which propose potential solutions to the world ecological crisis. However these frameworks may not always be founded on a good, or realistic understanding of the underlying ecological principles, or are over simplified by designers who do not have sufficient understanding of the ecological processes that underpin them. This paper describes some recent activities of the newly formed Sustainable Product Design Research Group at AUT, and presents a recently initiated staff research project to illustrate the role of Universities can play in engaging in the debate around developing a more sustainable future. In this project rapid prototyping product development processes are used as the primary methods with which to explore a recently developed sustainable design approach

Efficient fault tree analysis using binary decision diagrams

The Binary Decision Diagram (BDD) method has emerged as an alternative to conventional techniques for performing both qualitative and quantitative analysis of fault trees. BDDs are already proving to be of considerable use in reliability analysis, providing a more efficient means of analysing a system, without the need for the approximations previously used in the traditional approach of Kinetic Tree Theory. In order to implement this technique, a BDD must be constructed from the fault tree, according to some ordering of the fault tree variables. The selected variable ordering has a crucial effect on the resulting BDD size and the number of calculations required for its construction; a bad choice of ordering can lead to excessive calculations and a BDD many orders of magnitude larger than one obtained using an ordering more suited to the tree. Within this thesis a comparison is made of the effectiveness of several ordering schemes, some of which have not previously been investigated. Techniques are then developed for the efficient construction of BDDs from fault trees. The method of Faunet reduction is applied to a set of fault trees and is shown to significantly reduce the size of the resulting BDDs. The technique is then extended to incorporate an additional stage that results in further improvements in BDD size. A fault tree analysis strategy is proposed that increases the likelihood of obtaining a BDD for any given fault tree. This method implements simplification techniques, which are applied to the fault tree to obtain a set of concise and independent subtrees, equivalent to the original fault tree structure. BDDs are constructed for each subtree and the quantitative analysis is developed for the set of BDDs to obtain the top event parameters and the event criticality functions

Design for Biodiversity: a new approach for ecologically sustainable product design?

McDonough and Braungart proposed the “Cradle to Cradle” design framework to provide solutions to the world’s current ecological crisis. This approach, based on examples from nature, ensures that human activities can have a positive ecological footprint, capable of replenishing and regenerating natural systems, as well guaranteeing that we are able to develop a world that is culturally and ecologically diverse. In their framework they describe the notion of biological nutrients, where industrial waste (non toxic & biodegradable) may be used as a beneficial nutrient for ecological systems, eliminating the need for efficiency, as “waste is good”. Consequently, Cradle to Cradle industrial systems will benefit the environment. A group of New Zealand scientists were asked to evaluate ‘Cradle to Cradle’ in an attempt to determine the potential of this approach for the sustainable design of products. Analysis of interview data indicated that sustainability is a complex and multifaceted concept, especially with regard to practical applications. In particular, understanding the input of biological nutrients into the environment was identified as being critically important. Furthermore, science can play an important in understanding the impacts of products, as well as how biological nutrient’s may be best used in environmental systems. The insights gathered from these interviews were used to explore the potential for an alternative sustainable design approach, which builds upon McDonough and Braungart’s concept of a biological nutrient, and aims to support the design of products that have a strong ecological foundation. Consequently, Design for Biodiversity is outlined as a potential approach for designing environmentally sustainable products. During the development of this approach, the relationship between science and design was explored to support the notion that ecosystems are the basis of human consumption and should be incorporated as an integral part of society to ensure the development of strong sustainability. The intent of this approach is to help to design ecologically beneficial products. It is relatively untested, and should be evaluated and revised during future design projects

Scale – Time – Complexity: engaging, entangling, and communicating ecology

This project proposes a forum for discussion that questions how we engage with our ecology. The panel will be framed within an acknowledgment of scale, time, and complexity as an entry point into a conversation about our local ecology and the universe beyond. The panellists’ aim to initiate a dialogue by situating the discussion around their own art and design research practices. These practices have emerged from local investigations into ecological issues that evolved into two overlapping research clusters, Art and Ecology, and Design and Innovation for Sustainability, at AUT University, in Auckland New Zealand. In our first collaborative project we explore how we might connect with and communicate ‘ecology’, in methods and practice that recognizes and embraces scale, time and complexity as a tactic into the subject, rather than as a barrier to engagement and the development of potential solutions

Single-phase laminar flow heat transfer from confined electron beam enhanced surfaces

An experimental investigation of the thermal-hydraulic characteristics for single-phase flow through three electron beam enhanced structures was conducted with water at mass flow rates from 0.005 kg/s to 0.045 kg/s. The structures featured copper heat transfer surfaces, approximately 28 mm wide and 32 mm long in the flow direction, with complex three-dimensional (3D) electron beam manufactured pyramid-like structures. The channel height varied depending on the height of the protrusions and the tip clearance was maintained at 0.1-0.3 mm. The average protrusion densities for the three samples S1, S2, and S3 were 13, 11, and 25 per cm2 with protrusion heights of 2.5, 2.8, and 1.6 mm, respectively. The data gathered were compared to those for a smooth channel surface operating under similar conditions. The results show an increase up to approximately three times for the average Nusselt number compared with the smooth surface. This is attributed to the surface irregularities of the enhanced surfaces, which not only increase the heat transfer area but also improve mixing, disturb the thermal and velocity boundary layers, and reduce thermal resistance. The increase in heat transfer with the enhanced surfaces was accompanied by an increase of pressure drop, which has to be considered in design.The authors would like to acknowledge Dr Anita Buxton and Dr Bruce Dance of TWI for their contribution to this project and also EPSRC and TSB for funding the EngD programme and sponsoring the ASTIA collaborative research project that helped to develop the Electron Beam enhanced surfaces respectively

A fault tree analysis strategy using binary decision diagrams

The use of Binary Decision Diagrams (BDDs) in fault tree analysis provides both an accurate and efficient means of analysing a system. There is a problem however, with the conversion process of the fault tree to the BDD. The variable ordering scheme chosen for the construction of the BDD has a crucial effect on its resulting size and previous research has failed to identify any scheme that is capable of producing BDDs for all fault trees. This paper proposes an analysis strategy aimed at increasing the likelihood of obtaining a BDD for any given fault tree, by ensuring the associated calculations are as efficient as possible. The method implements simplification techniques, which are applied to the fault tree to obtain a set of 'minimal' subtrees, equivalent to the original fault tree structure. BDDs are constructed for each, using ordering schemes most suited to their particular characteristics. Quantitative analysis is performed simultaneously on the set of BDDs to obtain the top event probability, the system unconditional failure intensity and the criticality of the basic events

Fusion Protein of the Paramyxovirus SV5: Destabilizing and Stabilizing Mutants of Fusion Activation

AbstractThe fusion (F) protein of the paramyxovirus SV5 strain W3A causes syncytium formation without coexpression of the SV5 hemagglutinin-neuraminidase (HN) glycoprotein, whereas the F protein of the SV5 strain WR requires coexpression of HN for fusion activity. SV5 strains W3A and WR differ by three amino acid residues at positions 22, 443, and 516. The W3A F protein residues P22, S443, and V516 were changed to amino acids found in the WR F protein (L22, P443, and A516, respectively). Three single-mutants, three double-mutants, and the triple-mutant were constructed, expressed, and assayed for fusion using three different assays. Mutant P22L did not cause fusion under physiological conditions, but fusion was activated at elevated temperatures. Compared with the W3A F protein, mutant S443P enhanced the fusion kinetics with a faster rate and greater extent, and had a lower activation temperature. Mutant V516A had little effect on F protein-mediated fusion. The double-mutant P22L,S443P was capable of causing fusion, suggesting that the two mutations have opposing effects on fusion activation. The WR F protein requires coexpression of HN to cause fusion at 37°C, and does not cause fusion at 37°C when coexpressed with influenza virus hemagglutinin (HA); however, at elevated temperatures coexpression of WR F protein with HA resulted in fusion activation. In the crystal structure of the core trimer of the SV5 F protein (Baker, K. A., Dutch, R. E., Lamb, R.A., and Jardetzky, T. S. (1999). Mol. Cell 3, 309–319), S443 is the last residue (with interpretable electron density) in an extended chain region and the temperature factor for S443 is high, suggesting conformational flexibility at this point. Thus, the presence of prolines at residues 22 and 443 may destabilize the F protein and thereby decrease the energy required to trigger the presumptive conformational change to the fusion-active state