Damage diagnosis for complex steel truss bridges using multi-layer genetic algorithm

Considerate amount of research has proposed optimization-based approaches employing various vibration parameters for structural damage diagnosis. The damage detection by these methods is in fact a result of updating the analytical structural model in line with the current physical model. The feasibility of these approaches has been proven. But most of the verification has been done on simple structures, such as beams or plates. In the application on a complex structure, like steel truss bridges, a traditional optimization process will cost massive computational resources and lengthy convergence. This study presents a multi-layer genetic algorithm (ML-GA) to overcome the problem. Unlike the tedious convergence process in a conventional damage optimization process, in each layer, the proposed algorithm divides the GA’s population into groups with a less number of damage candidates; then, the converged population in each group evolves as an initial population of the next layer, where the groups merge to larger groups. In a damage detection process featuring ML-GA, as parallel computation can be implemented, the optimization performance and computational efficiency can be enhanced. In order to assess the proposed algorithm, the modal strain energy correlation (MSEC) has been considered as the objective function. Several damage scenarios of a complex steel truss bridge’s finite element model have been employed to evaluate the effectiveness and performance of ML-GA, against a conventional GA. In both single- and multiple damage scenarios, the analytical and experimental study shows that the MSEC index has achieved excellent damage indication and efficiency using the proposed ML-GA, whereas the conventional GA only converges at a local solution.

Fragrance of night and the hybridisation of Indonesian crime fiction

The novel manuscript Fragrance of Night is a crime novel set in Indonesia. Raymond Chan, struggling to deal with the death of his Australian wife, returns to his country of birth, Indonesia. Ostensibly he returns to attend his cousin Lee’s wedding but he is also in search of some meaning in his life. He is drawn into a local murder mystery, and with the help of a young, Javanese policeman, he is soon investigating suspects and motives. Raymond finds himself becoming increasingly enamoured with the main suspect, Lani, but ultimately, once the murder mystery is solved, Raymond loses her. The exegesis examines crime fiction as a genre, in particular Indonesian crime fiction and notions of postcolonialism and hybridisation. Within this broader context, it analyses works by Indonesian crime fiction writer S Mara Gd, postcolonial crime fiction and novels written in English but set in ‘exotic’ locale. The formulation of my novel Fragrance of Night was informed by the examination of the machinations of hybridised crime fiction and the more general rules of the crime fiction genre.

Mortality and cost outcomes of elderly trauma patients admitted to intensive care and the general wards of an Australian tertiary referral hospital

Mortality and cost outcomes of elderly intensive care unit (ICU) trauma patients were characterised in a retrospective cohort study from an Australian tertiary ICU. Trauma patients admitted between January 2000 and December 2005 were grouped into three major age categories: aged ≥65 years admitted into ICU (n=272); aged ≥65 years admitted into general ward (n=610) and aged <65 years admitted into ICU (n=1617). Hospital mortality predictors were characterised as odds ratios (OR) using logistic regression. The impact of predictor variables on (log) total hospital-stay costs was determined using least squares regression. An alternate treatment-effects regression model estimated the mortality cost-effect as an endogenous variable. Mortality predictors (P ≤0.0001, comparator: ICU ≥65 years, ventilated) were: ICU <65 not-ventilated (OR 0.014); ICU <65 ventilated (OR 0.090); ICU age ≥65 not-ventilated (OR 0.061) and ward ≥65 (OR 0.086); increasing injury severity score and increased Charlson comorbidity index of 1 and 2, compared with zero (OR 2.21 [1.40 to 3.48] and OR 2.57 [1.45 to 4.55]). The raw mean daily ICU and hospital costs in A$ 2005 (US$) for age <65 and ≥65 to ICU, and ≥65 to the ward were; for year 2000: ICU, $2717 (1462) and $2777 (1494); hospital, $1837 (988) and $1590 (855); ward $933 (502); for year 2005: ICU, $3202 (2393) and $3086 (2307); hospital, $1938 (1449) and $1914 (1431); ward $1180 (882). Cost increments were predicted by age ≥65 and ICU admission, increasing injury severity score, mechanical ventilation, Charlson comorbidity index increments and hospital survival. Mortalitycost-effect was estimated at -63% by least squares regression and -82% by treatment-effects regression model. Patient demographic factors, injury severity and its consequences predict both cost and survival in trauma. The cost mortality effect was biased upwards by conventional least squares regression estimation.

Susceptibility of the critical structural components of railway bridges to the changes in train speed

Modern trains with different axle configurations, speeds and loads are used in railway networks. As a result, one of the most important questions of the mangers involved in bridge managements systems (BMS) is how these changes affect the structural behavior of the critical components of the railway bridges. Although researchers have conducted, many investigations on the dynamic effects of the moving loads on bridges, the influence of the changes in the speed of the train on the demand by capacity ratios of the different critical components of the bridge have not yet been properly studied. This study is important, because different components with different capacities and roles for carrying loads in the structure may be affected differently. To investigate the above phenomenon in this research, a structural model of a simply supported bridge is developed. It will be verified that the dynamic behavior of this bridge is similar to a group of railway bridges in Australia. Demand by capacity ratios of the critical components of the bridge, when it is subjected to a train load with different speeds will be calculated. The results show that the effect of increase or decrease of speed should not be underestimated. The outcome is very significant as it is contrary to what is currently expected, i.e. by reducing the speed of the train, the demand by capacity ratio of components may increase and make the bridge unsafe for carrying live load.

Nursing research : the Australian College of Nursing position statement

Background Nursing perspectives play an important role in addressing the health priorities of today’s society. The Australian College of Nursing (ACN) acknowledges the significant contribution that nursing research has made since the first nurse researcher, Florence Nightingale, documented the factors that affected the morbidity and mortality of soldiers wounded in the Crimean war in the 1800s. The nursing profession continues to celebrate the significant contribution nursing research made to improving nursing practice and health outcomes. These significant contributions over recent years include, but are not limited to: 1. Health services research that has demonstrated the importance of nursing services and how such services are designed/organised to ensure safety and quality of care (Duffield, et al., 2011; Fernandez, et al., 2012; Middleton, et al., 2011); 2. Clinical research that has demonstrated the value of specific nursing interventions to improved health outcomes, including enhanced survival, reduced morbidity, and improved quality of life and consumer engagement (Cancer Australia and Cancer Voices Australia, 2011; Kitson, et al., 2013; Middleton, et al., 2012; Rickard, et al., 2012; Zeitz, et al., 2011); 3. Basic science research that has advanced discoveries in terms of understanding the biological mechanisms underpinning nursing interventions (Illi, et al., 2012; Kim, et al., 2012; Miaskowski, et al., 2010; Simonova, et al., 2012); 4. Epidemiological research that has advanced understanding about how individuals and populations respond to health problems (Carrington, et al., 2012); 5. Qualitative research that has advanced understanding about experiences of and responses to health and illness and the processes of care that are important to optimal outcomes (Schulman-Green, et al., 2012; Scott, et al., 2011).

Do nursing interventions targeting concurrent symptoms hold promise for managing fatigue in patients with advanced cancer?

TO THE EDITOR: It was with great interest that I read two recent articles by de Raaf et al1, and Bruera et al2. These authors are to be congratulated for completing two of the very few high quality randomized trials that evaluate complex interventions for managing fatigue in patients with advanced cancer. de Raaf et al conducted a non-blinded RCT with 152 patients with advanced cancer and reported significant reduction of fatigue in patients who received a nurse-led monitoring and protocol-guided treatment of physical symptoms compared with those who received usual care1. Patients who received this intervention experienced a significant improvement over time in general fatigue, at one-month follow-up and two-month follow-up. Another recent RCT conducted with 141 patients with advanced cancer by Bruera et al2 did not find any benefits of a nursing telephone intervention that involved systematic symptom assessment/management, medication review, psychosocial support and patient education in fatigue reduction, compared to those who received a control telephone intervention conducted by a non-professional...

Towards better end-of-life care : a major opportunity for nurses to contribute to the debate

Integrated care pathways are documents which outline the essential steps of multidisciplinary care in addressing a specific clinical problem (Rotter et al., 2010). They can be used to introduce clinical guidelines and systematic audits of clinical practice, and to ensure that the most appropriate management occurs at the most appropriate time and that it is provided by the most appropriate health professional. The Liverpool Care Pathway (LCP) is an example of an integrated care pathway, designed in the 1990s to guide care for people who are in their last days of life (Ellershaw et al., 1997, Ellershaw and Ward, 2003)...

Very sensitive fiber Bragg grating accelerometer using transverse forces with an easy over-range protection and low cross axial sensitivity

The first fiber Bragg grating (FBG) accelerometer using direct transverse forces is demonstrated by fixing the FBG by its two ends and placing a transversely moving inertial object at its middle. It is very sensitive because a lightly stretched FBG is more sensitive to transverse forces than axial forces. Its resonant frequency and static sensitivity are analyzed by the classic spring-mass theory, assuming the axial force changes little. The experiments show that the theory can be modified for cases where the assumption does not hold. The resonant frequency can be modified by a linear relationship experimentally achieved, and the static sensitivity by an alternative method proposed. The principles of the over-range protection and low cross axial sensitivity are achieved by limiting the movement of the FBG and were validated experimentally. The sensitivities 1.333 and 0.634 nm/g were experimentally achieved by 5.29 and 2.83 gram inertial objects at 10 Hz from 0.1 to 0.4 g (g = 9.8 m/s 2), respectively, and their resonant frequencies were around 25 Hz. Their theoretical static sensitivities and resonant frequencies found by the modifications are 1.188 nm/g and 26.81 Hz for the 5.29 gram one and 0.784 nm/g and 29.04 Hz for the 2.83 gram one, respectively.

A statistical strategy to select optimal structural health monitoring data in operational modal analysis

Operational modal analysis (OMA) is prevalent in modal identifi cation of civil structures. It asks for response measurements of the underlying structure under ambient loads. A valid OMA method requires the excitation be white noise in time and space. Although there are numerous applications of OMA in the literature, few have investigated the statistical distribution of a measurement and the infl uence of such randomness to modal identifi cation. This research has attempted modifi ed kurtosis to evaluate the statistical distribution of raw measurement data. In addition, a windowing strategy employing this index has been proposed to select quality datasets. In order to demonstrate how the data selection strategy works, the ambient vibration measurements of a laboratory bridge model and a real cable-stayed bridge have been respectively considered. The analysis incorporated with frequency domain decomposition (FDD) as the target OMA approach for modal identifi cation. The modal identifi cation results using the data segments with different randomness have been compared. The discrepancy in FDD spectra of the results indicates that, in order to fulfi l the assumption of an OMA method, special care shall be taken in processing a long vibration measurement data. The proposed data selection strategy is easy-to-apply and verifi ed effective in modal analysis.

Fraud risk and the visibility of carbon

In recent years, carbon has been increasingly rendered ‘visible’ both discursively and through political processes that have imbued it with economic value. Greenhouse gas (GHG) emissions have been constructed as social and environmental costs and their reduction or avoidance as social and economic gain. The ‘marketisation’ of carbon, which has been facilitated through various compliance schemes such as the European Union Emissions Trading Scheme (EU ETS), the Kyoto Protocol, the proposed Australian Emissions Reduction Scheme and through the voluntary carbon credit market, have attempted to bring carbon into the ‘foreground’ as an economic liability and/or opportunity. Accompanying the increasing economic visibility of carbon are reports of frauds and scams – the ‘gaming of carbon markets’(Chan 2010). As Lohmann (2010: 21) points out, ‘what are conventionally classed as scams or frauds are an inevitable feature of carbon offset markets, not something that could be eliminated by regulation targeting the specific businesses or state agencies involved’. This paper critiques the disparate discourses of fraud risk in carbon markets and examines cases of fraud within emerging landscapes of green criminology.

Role of the apolipoprotein E and catechol-O-methyltransferase genes in prospective and retrospective memory traits

Human memory is a complex neurocognitive process. By combining psychological and molecular genetics expertise, we examined the APOE ε4 allele, a known risk factor for Alzheimer's disease, and the COMT Val 158 polymorphism, previously implicated in schizophrenia, for association with lowered memory functioning in healthy adults. To assess memory type we used a range of memory tests of both retrospective and prospective memory. Genotypes were determined using RFLP analysis and compared with mean memory scores using univariate ANOVAs. Despite a modest sample size (n=197), our study found a significant effect of the APOE ε4 polymorphism in prospective memory. Supporting our hypothesis, a significant difference was demonstrated between genotype groups for means of the Comprehensive Assessment of Prospective Memory total score (p=0.036; ε4 alleles=1.99; all other alleles=1.86). In addition, we demonstrate a significant interactive effect between the APOE ε4 and COMT polymorphisms in semantic memory. This is the first study to investigate both APOE and COMT genotypes in relation to memory in non-pathological adults and provides important information regarding the effect of genetic determinants on human memory.

A pre-post evaluation of an ambulatory nutrition support service for malnourished patients post hospital discharge: a pilot study

Introduction Malnutrition is common among hospitalised patients, with poor follow-up of nutrition support post-discharge. Published studies on the efficacy of ambulatory nutrition support (ANS) for malnourished patients post-discharge are scarce. The aims of this study were to evaluate the rate of dietetics follow-up of malnourished patients post-discharge, before (2008) and after (2010) implementation of a new ANS service, and to evaluate nutritional outcomes post-implementation. Materials and Methods Consecutive samples of 261 (2008) and 163 (2010) adult inpatients referred to dietetics and assessed as malnourished using Subjective Global Assessment (SGA) were enrolled. All subjects received inpatient nutrition intervention and dietetic outpatient clinic follow-up appointments. For the 2010 cohort, ANS was initiated to provide telephone follow-up and home visits for patients who failed to attend the outpatient clinic. Subjective Global Assessment, body weight, quality of life (EQ-5D VAS) and handgrip strength were measured at baseline and five months post-discharge. Paired t-test was used to compare pre- and post-intervention results. Results In 2008, only 15% of patients returned for follow-up with a dietitian within four months post-discharge. After implementation of ANS in 2010, the follow-up rate was 100%. Mean weight improved from 44.0 ± 8.5kg to 46.3 ± 9.6kg, EQ-5D VAS from 61.2 ± 19.8 to 71.6 ± 17.4 and handgrip strength from 15.1 ± 7.1 kg force to 17.5 ± 8.5 kg force; p<0.001 for all. Seventy-four percent of patients improved in SGA score. Conclusion Ambulatory nutrition support resulted in significant improvements in follow-up rate, nutritional status and quality of life of malnourished patients post-discharge.

Do palliative care health professionals settle for low level evidence?

The findings of the recent independent review of the UK Liverpool Care Pathway (LCP)1, following substantial concerns raised by members of the public and health professionals found that the implementation of the LCP is often associated with poor care1. The Neuberger Report highlighted the complexity of various ethical, safety, clinical practice and negligence issues associated with pathway usage and how, despite technological advances, diagnosing dying continues to be challenging. The UK Government’s decision to phase out the LCP as policy following these findings, has generated considerable debate both within and beyond the UK. However, another key issue raised by the Neuberger’s report is the issue of the palliative care community’s perceived willingness to readily adopt new clinical practices in the absence of evidence. It is this translational issue that this editorial explores.

A new method for quantifying the contribution of different critical agents on railway bridge deterioration

Railway Bridges deteriorate over time due to different critical factors including, flood, wind, earthquake, collision, and environment factors, such as corrosion, wear, termite attack, etc. In current practice, the contributions of the critical factors, towards the deterioration of railway bridges, which show their criticalities, are not appropriately taken into account. In this paper, a new method for quantifying the criticality of these factors will be introduced. The available knowledge as well as risk analyses conducted in different Australian standards and developed for bridge-design will be adopted. The analytic hierarchy process (AHP) is utilized for prioritising the factors. The method is used for synthetic rating of railway bridges developed by the authors of this paper. Enhancing the reliability of predicting the vulnerability of railway bridges to the critical factors, will be the significant achievement of this research.

Malnutrition and its impact on cost of hospitalization, length of stay, readmission and 3-year mortality

Background & aims The confounding effect of disease on the outcomes of malnutrition using diagnosis-related groups (DRG) has never been studied in a multidisciplinary setting. This study aims to determine the impact of malnutrition on hospitalisation outcomes, controlling for DRG. Methods Subjective Global Assessment was used to assess the nutritional status of 818 patients within 48 hours of admission. Prospective data were collected on cost of hospitalisation, length of stay (LOS), readmission and mortality up to 3 years post-discharged using National Death Register data. Mixed model analysis and conditional logistic regression matching by DRG were carried out to evaluate the association between nutritional status and outcomes, with the results adjusted for gender, age and race. Results Malnourished patients (29%) had longer hospital stays (6.9±7.3 days vs. 4.6±5.6 days, p<0.001) and were more likely to be readmitted within 15 days (adjusted relative risk = 1.9, 95%CI 1.1–3.2, p=0.025). Within a DRG, the mean difference between actual cost of hospitalisation and the average cost for malnourished patients was greater than well-nourished patients (p=0.014). Mortality was higher in malnourished patients at 1 year (34% vs. 4.1 %), 2 years (42.6% vs. 6.7%) and 3 years (48.5% vs. 9.9%); p<0.001 for all. Overall, malnutrition was a significant predictor of mortality (adjusted hazard ratio = 4.4, 95%CI 3.3-6.0, p<0.001). Conclusions Malnutrition was evident in up to one third of inpatients and led to poor hospitalisation outcomes, even after matching for DRG. Strategies to prevent and treat malnutrition in the hospital and post-discharge are needed.