On this Writing : An Autotheoretic Account

An invited chapter that provides an autobiographical account of 'critical incidents' in becoming an academic writer.

The effect of bone graft type on fusion rates following anterior thoracoscopic scoliosis correction

Bone graft is generally considered fundamental in achieving solid fusion in scoliosis correction and pseudarthrosis following instrumentation may predispose to implant failure. In thoracoscopic anterior-instrumented scoliosis surgery, autologous rib or iliac crest graft has been utilised traditionally but both techniques increase operative duration and cause donor site morbidity. Allograft bone and bone morphogenetic protein (BMP) alternatives may improve fusion rates but this remains controversial. This study's objective was to compare two-year postoperative fusion rates in a series of patients who underwent thoracoscopic anterior instrumentation for thoracic scoliosis utilising various bone graft types.

On-road ultrafine particle concentration in the M5 East road tunnel, Sydney, Australia

The human health effects following exposure to ultrafine (<100nm) particles (UFPs) produced by fuel combustion, while not completely understood, are generally regarded as detrimental. Road tunnels have emerged as locations where maximum exposure to these particles may occur for the vehicle occupants using them. This study aimed to quantify and investigate the determinants of UFP concentrations in the 4km twin-bore (eastbound and westbound) M5 East tunnel in Sydney, Australia. Sampling was undertaken using a condensation particle counter (CPC) mounted in a vehicle traversing both tunnel bores at various times of day from May through July, 2006. Supplementary measurements were conducted in February, 2008. Over three hundred transects of the tunnel were performed, and these were distributed evenly between the bores. Additional comparative measurements were conducted on a mixed route comprising major roads and shorter tunnels, all within Sydney. Individual trip average UFP concentrations in the M5 East tunnel bores ranged from 5.53 × 104 p cm-3 to 5.95 × 106 p cm-3. Data were sorted by hour of capture, and hourly median trip average (HMA) UFP concentrations ranged from 7.81 × 104 p cm-3 to 1.73 × 106 p cm-3. Hourly median UFP concentrations measured on the mixed route were between 3.71 × 104 p cm-3 and 1.55 × 105 p cm-3. Hourly heavy diesel vehicle (HDV) traffic volume was a very good determinant of UFP concentration in the eastbound tunnel bore (R2 = 0.87), but much less so in the westbound bore (R2 = 0.26). In both bores, the volume of passenger vehicles (i.e. unleaded gasoline-powered vehicles) was a significantly poorer determinant of particle concentration. When compared with similar studies reported previously, the measurements described here were among the highest recorded concentrations, which further highlights the contribution road tunnels may make to the overall UFP exposure of vehicle occupants.

Submission to the House of Representatives Standing Committee on Environment and Heritage : Inquiry into a Sustainability Charter by the Cooperative Research Centre for Construction Innovation

The Cooperative Research Centre for Construction Innovation1 (hereafter called Construction Innovation) supports the notion of the establishment of a Sustainability Charter for Australia and is interested in working collaboratively to achieve this outcome. A number of challenges need to be addressed to develop this Charter. This submission outlines these challenges and possible responses to them by a Sustainability Commission.

How the whiteness embedded in health services impacts on the health and well-being of Aboriginal peoples

Aboriginal women are treated differently by non-indigenous health care providers based on perceptions of Aboriginality and skin colour and white race privilege within health care environments. The experiences shared below are from some of the Aboriginal woman respondents in a research project undertaken within Rockhampton, a regional area in Central Queensland (Fredericks, 2003). The experiences give an insight into how the Aboriginal women interviewed felt and their observations of how other Aboriginal women were treated within health care settings based on skin colour and perceptions of Aboriginality. A number of the women demonstrated a personal in-depth analysis of the issues surrounding place, skin colour and Aboriginality. For example, one of the women, who I named Kay, identified one particular health service organisation and stated that, ‘it is a totally white designed space. There is nothing that identifies me to that place. I just won’t go there as a client because I don’t feel they cater for me as a black woman’. Kay’s words give us an understanding of the reality experienced by Aboriginal women as they move in and out of places within health environments and broader society. Some of these experiences are examples of direct racism, whilst other examples are subtle and demonstrate how whiteness manifests and plays out within places. I offer acknowledgement and honour to the Aboriginal women who shared their stories and gave me a glimpse of their realities in the research project from which the findings presented in this chapter are taken. It is to this research project that is the subject of this chapter.

Completing the jigsaw : ESL and EFL undergraduate views on interactive peer-based learning

English as a Second Language (ESL) and English as a Foreign Language (EFL) students often face incongruence with Western teaching methods and learning expectations. The aim of this paper is to explore the potential for interactive peer-based learning to engage ESL and EFL language learners provide authentic communication experiences and accelerate learning through two case studies in different contexts. A study was undertaken to investigate student ‘voice’ (Rudduck, 1999, 2005; Rudduck & Flutter, 2004) during an intervention of communicative language teaching using peer-based learning strategies. This article describes unique similarities and subtle differences between ESL and EFL undergraduate learning in two different cultural contexts, using a 'stages of learning matrix' teaching tool to encourage civic skills and self-efficacy. It also suggests ways for teachers to improve on inconsistencies in group-based learning in order to promote more inclusive and congruent learning experiences for English language learners.

Fall of a transfemoral amputee fitted with osseointegrated fixation : loading impact on residuum

This study presented the characteristics of the loading impact on the residuum of a transfemoral amputee fitted with an osseointegrated fixation during a fall for the first time. The maximum force (1,145 N = 132 % of the body weight and moments (153 N.m) were applied on the long and medio-lateral axes, respectively, approximately 0.85 s after heel contact of the prosthesis.

Loading applied on prosthetic knee of transfemoral amputee: comparison of inverse dynamics and direct measurements

Inverse dynamics is the most comprehensive method that gives access to the net joint forces and moments during walking. However it is based on assumptions (i.e., rigid segments linked by ideal joints) and it is known to be sensitive to the input data (e.g., kinematic derivatives, positions of joint centres and centre of pressure, inertial parameters). Alternatively, transducers can be used to measure directly the load applied on the residuum of transfemoral amputees. So, the purpose of this study was to compare the forces and moments applied on a prosthetic knee measured directly with the ones calculated by three inverse dynamics computations - corresponding to 3 and 2 segments, and « ground reaction vector technique » - during the gait of one patient. The maximum RMSEs between the estimated and directly measured forces (i.e., 56 N) and moment (i.e., 5 N.m) were relatively small. However the dynamic outcomes of the prosthetic components (i.e., absorption of the foot, friction and limit stop of the knee) were only partially assessed with inverse dynamic methods.

Faster group operations on elliptic curves

This paper improves implementation techniques of Elliptic Curve Cryptography. We introduce new formulae and algorithms for the group law on Jacobi quartic, Jacobi intersection, Edwards, and Hessian curves. The proposed formulae and algorithms can save time in suitable point representations. To support our claims, a cost comparison is made with classic scalar multiplication algorithms using previous and current operation counts. Most notably, the best speeds are obtained from Jacobi quartic curves which provide the fastest timings for most scalar multiplication strategies benefiting from the proposed 12M + 5S + 1D point doubling and 7M + 3S + 1D point addition algorithms. Furthermore, the new addition algorithm provides an efficient way to protect against side channel attacks which are based on simple power analysis (SPA). Keywords: Efficient elliptic curve arithmetic,unified addition, side channel attack.

Faster pairings on special Weierstrass curves

This paper presents efficient formulas for computing cryptographic pairings on the curve y 2 = c x 3 + 1 over fields of large characteristic. We provide examples of pairing-friendly elliptic curves of this form which are of interest for efficient pairing implementations.

Certainties and uncertainties : ethics and professional identities of early childhood educators

This study is an inquiry into the professional identity constructions of early childhood educators, where identity is conceptualised as social and contextual. Through a genealogical analysis of narratives of four Queensland early childhood teachers, the thesis renders as problematic universal and fixed notions of what it is to be an early childhood professional. The data are the four teachers’ professional life history narratives recounted through a series of conversational interviews with each participant. As they spoke about professionalism and ethics, these teachers struggled to locate themselves as professionals, as they drew on a number of dominant discourses available to them. These dominant discourses were located and mapped through analysis of the participants’ talk about relationships with parents, colleagues and authorities. Genealogical analysis enabled multiple readings of the ways in which the participants’ talk held together certainties and uncertainties, as they recounted their experiences and spoke of early childhood expertise, relational engagement and ethics. The thesis concludes with suggestions for ways to support early childhood teachers and pre-service teachers to both engage with and resist normative processes and expectations of professional identity construction. In so doing, multiple and contextual opportunities can be made available when it comes to being professional and ‘doing’ ethics. The thesis makes an argument for new possibilities for thinking and speaking professional identities that include both certainty and uncertainty, comfort and discomfort, and these seemingly oppositional terms are held together in tension, with an insistence that both are necessary and true. The use of provocations offers tools through which pre-service teachers, teachers and teacher educators can access new positions associated with certainties and uncertainties in professional identities. These new positions call for work that supports experiences of ‘de-comfort’ – that is, experiences that encourage early childhood educators to step away from the comfort zones that can become part of expertise, professional relationships and ethics embedded within normative representations of what it is to be an early childhood professional.

Heavy truck suspension optimization based on modified skyhook damping control

This paper presents a multi-objective optimization strategy for heavy truck suspension systems based on modified skyhook damping (MSD) control, which improves ride comfort and road-friendliness simultaneously. A four-axle heavy truck-road coupling system model was established using functional virtual prototype technology; the model was then validated through a ride comfort test. As the mechanical properties and time lag of dampers were taken into account, MSD control of active and semi-active dampers was implemented using Matlab/Simulink. Through co-simulations with Adams and Matlab, the effects of passive, semi-active MSD control, and active MSD control were analyzed and compared; thus, control parameters which afforded the best integrated performance were chosen. Simulation results indicated that MSD control improves a truck’s ride comfort and roadfriendliness, while the semi-active MSD control damper obtains road-friendliness comparable to the active MSD control damper.

Data mining on prices of highway project main material based on WEB

The management of main material prices of provincial highway project quota has problems of lag and blindness. Framework of provincial highway project quota data MIS and main material price data warehouse were established based on WEB firstly. Then concrete processes of provincial highway project main material prices were brought forward based on BP neural network algorithmic. After that standard BP algorithmic, additional momentum modify BP network algorithmic, self-adaptive study speed improved BP network algorithmic were compared in predicting highway project main prices. The result indicated that it is feasible to predict highway main material prices using BP NN, and using self-adaptive study speed improved BP network algorithmic is the relatively best one.

A study of Chinese private passenger cars based on BP neural network

This study employs BP neural network to simulate the development of Chinese private passenger cars. Considering the uncertain and complex environment for the development of private passenger cars, indicators of economy, population, price, infrastructure, income, energy and some other fields which have major impacts on it are selected at first. The network is proved to be operable to simulate the progress of chinese private passenger cars after modeling, training and generalization test. Based on the BP neural network model, sensitivity analysis of each indicator is carried on and shows that the sensitivity coefficients of fuel price change suddenly. This special phenomenon reveals that the development of Chinese private passenger cars may be seriously affected by the recent high fuel price. This finding is also consistent with facts and figures

A study on matching and multi-objective fuzzy control strategy of heavy truck suspension system

Matching method of heavy truck-rear air suspensions is discussed, and a fuzzy control strategy which improves both ride comfort and road friendliness of truck by adjusting damping coefficients of the suspension system is found. In the first place, a Dongfeng EQ1141G7DJ heavy truck’s ten DOF whole vehicle-road model was set up based on Matlab/Simulink and vehicle dynamics. Then appropriate passive air suspensions were chosen to replace the original rear leaf springs of the truck according to truck-suspension matching criterions, consequently, the stiffness of front leaf springs were adjusted too. Then the semi-active fuzzy controllers were designed for further enhancement of the truck’s ride comfort and the road friendliness. After the application of semi-active fuzzy control strategy through simulation, is was indicated that both ride comfort and road friendliness could be enhanced effectively under various road conditions. The strategy proposed may provide theory basis for design and development of truck suspension system in China.