Engineering the surface of a sugarcane roller mill roll for grip and durability

Roller mills are typically used to crush sugarcane to express the juice from which sugar is manufactured. The mill rolls need to provide sufficient grip to ensure minimal sliding of the sugarcane along the roll surface. The rolls are subject to pressures up to 55 MPa from the sugarcane bagasse (as the sugarcane is called after first being crushed between a pair of rolls). The insoluble component of sugarcane includes typically 10% ash that largely originates from soil that is harvested with the cane. The sugarcane juice is acidic with pH typically between 5.0 and 5.5. As a result of ash and juice, the mill rolls are subjected to a range of abrasive and corrosive wear mechanisms. Solutions to provide grip and resist wear involve the selection of an appropriate roll shell material and compatible hard facing to provide the desired grip and wear characteristics. This paper reviews the various solutions that have been adopted for grip and durability for mill rolls and highlights the advantages and disadvantages of each method.

Strengthening critical health psychology : a critical action orientation

The commentaries on my original article ‘The Emergence of Critical Health Psychology: Can it Contribute to Promoting Public Health?’ provided engaging views on what critical health psychology (CHP) actually is and does. Consideration of each commentary gave rise to numerous themes and generated my own further thoughts on CHP which I frame as five key areas of a continuing dialogue: (1) reflexivity and CHP; (2) health psychology: pluralist or not? (3) CHP as a moral project; (4) social action and change; and (5) strengthening critical approaches to health. Throughout I highlight concepts and issues that are integral to the capacity of CHP to create a shift towards a reinvigorated action-orientated agenda.

Re-strengthening 20th century architectural heritage : A case study of Brisbane City Hall restoration

Restoring old buildings to conform the current building policies and standards is a great challenge to engineers and architects. The restoration of the Brisbane City Hall, a heritage building listed by the State of Queensland in Australia, developed an innovative approach to upgrade the building using the method called ‘concrete overlay’ following the guidelines of both the International Council on Monuments and Sites and the Burra Charter of Australia. Concrete overlay is a new method of structural strengthening by drilling new reinforcement and placing new concrete on top of the existing structure, akin to a bone transplant or bone grafting in the case of a human being. This method is popularly used for newer bridges which have suffered load stresses. However, this method had never been used on any heritage buildings which were built on different conditions and standards. The compatibility of this method is currently being monitored. Most of the modern historic buildings are rapidly deteriorating and require immediate interventions in order to be saved. As most of these heritage buildings are on the stage of advanced deterioration, significant attempts are being made and several innovations are being applied to upgrade these structures to conform with the current building requirements. To date, the knowledge and literature in regarding ‘concrete cancer’ in relation to rehabilitating these reinforced concrete heritage structures is significantly lacking. It is hoped that the method of concrete overlay and the case study of Brisbane City Hall restoration will contribute to the development of restoration techniques and policies for Modern Heritage Buildings.

Re-strengthening Brisbane City Hall

The restoration of Brisbane City Hall is an indication of a society that acknowledges the significance of cultural heritage. Preserving this historical icon required significant funding support, so the rehabilitation process must be thoroughly analysed and validated.

Development and validation of a new self-report instrument for measuring sedentary behaviors and light-intensity physical activity in adults

Background Low levels of physical activity and high levels of sedentary behavior (SB) are major public health concerns. This study was designed to develop and validate the 7-day Sedentary (S) and Light Intensity Physical Activity (LIPA) Log (7-day SLIPA Log), a self-report measure of specific daily behaviors. Method To develop the log, 62 specific SB and LIPA behaviors were chosen from the Compendium of Physical Activities. Face-to-face interviews were conducted with 32 sedentary volunteers to identify domains and behaviors of SB and LIPA. To validate the log, a further 22 sedentary adults were recruited to wear the GT3X for 7 consecutive days and nights. Results Pearson correlations (r) between the 7-day SLIPA Log and GT3X were significant for sedentary (r =.86, p < 0.001), for LIPA (r =.80, p < 0.001). Lying and sitting postures were positively correlated with GT3X output (r =.60 and r =.64, p < 0.001, respectively). No significant correlation was found for standing posture (r =.14, p = 0.53).The kappa values between the 7-day SLIPA Log and GT3X variables ranged from 0.09–0.61, indicating poor to good agreement. Conclusion The 7-day SLIPA Log is a valid self-report measure of SB and LIPA in specific behavioral domains.

Assessing the suitability of existing spatial data for disaster planning and mitigation in Queensland

The Council of Australian Governments (COAG) in 2003 gave in-principle approval to a best-practice report recommending a holistic approach to managing natural disasters in Australia incorporating a move from a traditional response-centric approach to a greater focus on mitigation, recovery and resilience with community well-being at the core. Since that time, there have been a range of complementary developments that have supported the COAG recommended approach. Developments have been administrative, legislative and technological, both, in reaction to the COAG initiative and resulting from regular natural disasters. This paper reviews the characteristics of the spatial data that is becoming increasingly available at Federal, state and regional jurisdictions with respect to their being fit for the purpose for disaster planning and mitigation and strengthening community resilience. In particular, Queensland foundation spatial data, which is increasingly accessible by the public under the provisions of the Right to Information Act 2009, Information Privacy Act 2009, and recent open data reform initiatives are evaluated. The Fitzroy River catchment and floodplain is used as a case study for the review undertaken. The catchment covers an area of 142,545 km2, the largest river catchment flowing to the eastern coast of Australia. The Fitzroy River basin experienced extensive flooding during the 2010–2011 Queensland floods. The basin is an area of important economic, environmental and heritage values and contains significant infrastructure critical for the mining and agricultural sectors, the two most important economic sectors for Queensland State. Consequently, the spatial datasets for this area play a critical role in disaster management and for protecting critical infrastructure essential for economic and community well-being. The foundation spatial datasets are assessed for disaster planning and mitigation purposes using data quality indicators such as resolution, accuracy, integrity, validity and audit trail.

The role of customer gratitude in strengthening seller-buyer relationships

Despite its emphasis on relationships between buyers and sellers, and the effect of emotion on behaviours, marketing literature has not yet investigated customer gratitude as an element of relational exchange. Gratitude is a significant component of personal relationships and may offer important insights into how perceptions of relationship marketing investments impact customer trust in, satisfaction with and affective commitment to a seller. In addition, customer gratitude may provide a more complete explanation of how marketing investments work. Consequently, this research contributes to marketing literature by investigating customer gratitude as a mediating mechanism in the relationship between customer perceptions of relationship marketing investments and customer trust in, satisfaction with and affective commitment to the seller: all dimensions of relationship quality.

The impact of auditor independence regulations on established and emerging firms.

Purpose – The purpose of this paper is to study whether auditor independence reforms introduced in 2004 led to an enhancement in earnings quality in the post-reform era. Design/methodology/approach – This study predicts that as the cost of compliance will vary based on a firm's existing corporate governance regime and the level of external scrutiny (monitoring) it faces, we compare the earnings quality of a sample of “established” (S&P/ASX 100) to a sample of “emerging” (S&P/ASX Small Ordinaries Index) firms. The paper examines the reporting behaviour of the two groups of listed entities, covering the regulatory change period 2003-2006. The paper uses regression modelling to test the associations between increased audit independence, earnings quality and corporate governance mechanisms over the pre- and post-regulatory period. Findings – The paper's results confirm that earnings quality for the established firms was enhanced in the post-reform period; while this was not the case for emerging firms. The evidence also suggests that corporate governance mechanisms of board independence and board financial skill are associated with higher earnings quality; while the higher the concentration of insider firm ownership is associated with lower earnings quality. Practical implications – This study provides policy makers with evidence as to changes in reporting behaviour following law reform aimed at strengthening auditor independence. Originality/value – The studies on earnings quality are informed by the US market practices. Australia provides a unique setting through its auditor independence reforms to examine the impact of reform choices. This study also investigates two specific subsets of the market: established firms and emerging firms.

Re-strengthening Brisbane City Hall : a case study of heritage engineering

Upgrading old buildings with the evolution of building requirements, this project investigates new approaches that can be applied to strengthen our own heritage buildings using historical and comparative analysis of heritage building restorations locally and abroad. Within the newly developing field of Heritage Engineering, it evaluates the innovative Concrete Overlay technique adapted to building restoration of the Brisbane City Hall. This study aims to extend the application of Concrete Overlay techniques and determine its compatibility specifically to heritage buildings. Concrete overlay involves drilling new reinforcement and placing concrete on top of the existing structure. It is akin to a bone transplant or bone grafting in the case of a human being and has been used by engineers to strengthen newer bridges.

Hemi-field and full-field form-deprivation induce timing changes in multifocal ERG responses in chick

Purpose: In animal models hemi-field deprivation results in localised, graded vitreous chamber elongation and presumably deprivation induced localised changes in retinal processing. The aim of this research was to determine if there are variations in ERG responses across the retina in normal chick eyes and to examine the effect of hemi-field and full-field deprivation on ERG responses across the retina and at earlier times than have previously been examined electrophysiologically. Methods: Chicks were either untreated, wore monocular full-diffusers or half-diffusers (depriving nasal retina) (n = 6-8 each group) from day 8. mfERG responses were measured using the VERIS mfERG system across the central 18.2º× 16.7º (H × V) field. The stimulus consisted of 61 unscaled hexagons with each hexagon modulated between black and white according to a pseudorandom binary m-sequence. The mfERG was measured on day 12 in untreated chicks, following 4 days of hemi-field diffuser wear, and 2, 48 and 96 h after application of full-field diffusers. Results: The ERG response of untreated chick eyes did not vary across the measured field; there was no effect of retinal location on the N1-P1 amplitude (p = 0.108) or on P1 implicit time (p > 0.05). This finding is consistent with retinal ganglion cell density of the chick varying by only a factor of two across the entire retina. Half-diffusers produced a ramped retina and a graded effect of negative lens correction (p < 0.0001); changes in retinal processing were localized. The untreated retina showed increasing complexity of the ERG waveform with development; form-deprivation prevented the increasing complexity of the response at the 2, 48 and 96 h measurement times and produced alterations in response timing. Conclusions: Form-deprivation and its concomitant loss of image contrast and high spatial frequency images prevented development of the ERG responses, consistent with a disruption of development of retinal feedback systems. The characterisation of ERG responses in normal and deprived chick eyes across the retina allows the assessment of concurrent visual and retinal manipulations in this model. (Ophthalmic & Physiological Optics © 2013 The College of Optometrists.)

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.

Investigation into the bond between CFRP and steel tubes

CFRP material has been widely used to strengthen concrete structures. There is an increasing trend of using CFRP in strengthening steel structures. The bond between steel and CFRP is a key issue. Relatively less work has been done on the bond between CFRP and a curved surface which is often found in tubular structures. This paper reports a study on the bond between CFRP and steel tubes. A series of tensile tests were conducted with different bond lengths and number of layers. The types of adhesive and specimen preparation methods varied in the testing program. High modulus CFRP was used. Tests were carried out to measure the modulus and tensile strength of CFRP. Strain gages were mounted on different layers of CFRP. The stress distributions across the layers of the CFRP were established. Models were developed to estimate the maximum load for a given CFRP arrangement.

Recovering from the earthquake : early childhood teachers and children collaboratively telling stories about their experiences

Purpose – Traumatic events can cause post-traumatic stress disorder due to the severity of the often unexpected events. The purpose of this paper is to reveal how conversations around lived experiences of traumatic events, such as the Christchurch earthquake in February 2011, can work as a strategy for people to come to terms with their experiences collaboratively. By encouraging young children to recall and tell of their earthquake stories with their early childhood teachers they can begin to respond, renew, and recover (Brown, 2012), and prevent or minimise more stress being developed. Design/methodology/approach – The study involved collecting data of the participating children taking turns to wear a wireless microphone where their interactions with each other and with teachers were video recorded over one week in November 2011. A total of eight hours and 21 minutes of footage was collected; four minutes and 19 seconds of that footage are presented and analysed in this paper. The footage was watched repeatedly and transcribed using conversation analysis methods (Sacks, 1995). Findings – Through analysing the detailed turn-taking utterances between teachers and children, the orderliness of the co-production of remembering is revealed to demonstrate that each member orients to being in agreement about what actually happened. These episodes of story telling between the teachers and children demonstrate how the teachers encourage the children to tell about their experiences through actively engaging in conversations with them about the earthquake. Originality/value – The conversation analysis approach used in this research was found to be useful in investigating aspects of disasters that the participants themselves remember as important and real. This approach offers a unique insight into understanding how the earthquake event was experienced and reflected on by young children and their teachers, and so can inform future policy and provision in post-disaster situations.