939 resultados para high-breakdown regression


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The natural disasters incident that frequently hit Indonesia are floods, severe droughts, tsunamis, earth-quakes, volcano, eruptions, landslides, windstorm and forest fires. The impact of those natural disasters are significantly severe and affecting the quality of life of the community due to the breakdown of the public as-sets as one source to deliver public services. This paper is aimed to emphasis the importance of natural disaster risk-informed in relation to public asset management in Indonesian Central Government, particularly in asset planning stage where asset decision is made as the gate into the whole public asset management processes. A Case study in the Ministry of Finance Indonesia as the central government public asset manager and in 5 (five) line ministries/governmental agencies as public asset users was used as the approach to achieved the research objective. The case study devoured three data collection techniques i.e. interviews, observations and document archival which will be analysed by a content analysis approach. The result of the study indicates that Indonesian geographical position exposing many of public infra-structure assets as a high vulnerability to natural disasters. Information on natural-disaster trends and predictions to identify and measure the risks are available, however, such information are not utilise and integrated to the process of public infrastructure asset planning as the gate to the whole public asset management processes. Therefore, in order to accommodate and incorporate this natural disaster risk-information into public asset management processes, particularly in public asset planning, a public asset performance measurements framework should be adopted and applied in the process as one sources in making decision for infrastructure asset planning. Findings from this study provide useful input for the Ministry of Finance as public asset manager, scholars and private asset management practitioners in Indonesia to establish natural disaster risks awareness in public infrastructure asset management processes.

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Facial landmarks play an important role in face recognition. They serve different steps of the recognition such as pose estimation, face alignment, and local feature extraction. Recently, cascaded shape regression has been proposed to accurately locate facial landmarks. A large number of weak regressors are cascaded in a sequence to fit face shapes to the correct landmark locations. In this paper, we propose to improve the method by applying gradual training. With this training, the regressors are not directly aimed to the true locations. The sequence instead is divided into successive parts each of which is aimed to intermediate targets between the initial and the true locations. We also investigate the incorporation of pose information in the cascaded model. The aim is to find out whether the model can be directly used to estimate head pose. Experiments on the Annotated Facial Landmarks in the Wild database have shown that the proposed method is able to improve the localization and give accurate estimates of pose.

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Background: Few longitudinal studies have examined the mental health outcomes of women after abortion and the results are controversial. Despite falling birth rates, teenage pregnancies remain high and over half (53%) of teenage and a third (36%) of young adult (20_24 years) pregnancies are aborted. Recent findings from a NewZealand longitudinal birth cohort linked abortion and subsequent psychiatric disorders in young women. Limited Australian data is available examining this association. Methods: Data were taken from the Mater-University Study of Pregnancy (MUSP). Running since 1981, this is a prospective birth cohort study of 7223 mothers and children. At the 21-year follow-up 3775 (52.3% of the original cohort) participants were surveyed, of these 1132 young women had complete data on pregnancy outcomes and psychiatric diagnoses from a structured interview. Binary logistic regression examined the association between five lifetime psychiatric disorders (nicotine, alcohol, cannabis, affective and anxiety disorders) and ever having an abortion or birth. Analyses adjusted for age, concurrent and maternal sociodemographic factors, and factors related to adolescent behaviour, previous mental health and family functioning. Results: A quarter of the young women (n_261) reported at least one pregnancy and 32.6% had an abortion. Abortion was significantly associated with age-adjusted OR for all the lifetime disorders. After full adjustment abortion remained significantly associated with nicotine (OR_2.1, 1.2_3.6) and alcohol disorders (OR_2.0, 1.3_3.3). Conclusion: The findings suggest that abortion in young women is independently associated with an increased risk of nicotine and alcohol disorders.

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Background: Despite increasing diversity in pathways to adulthood, choices available to young people are influenced by environmental, familial and individual factors, namely access to socioeconomic resources, family support and mental and physical health status. Young people from families with higher socioeconomic position (SEP) are more likely to pursue tertiary education and delay entry to adulthood, whereas those from low socioeconomic backgrounds are less likely to attain higher education or training, and more likely to partner and become parents early. The first group are commonly termed ‘emerging adults’ and the latter group ‘early starters’. Mental health disorders during this transition can seriously disrupt psychological, social and academic development as well as employment prospects. Depression, anxiety and most substance use disorders have early onset during adolescence and early adulthood with approximately three quarters of lifetime psychiatric disorders having emerged by 24 years of age. Aims: This thesis aimed to explore the relationships between mental health, sociodemographic factors and family functioning during the transition to adulthood. Four areas were investigated: 1) The key differences between emerging adults and ‘early starters’, were examined and focused on a series of social, economic, and demographic factors as well as DSM-IV diagnoses; 2) Methodological issues associated with the measurement of depression and anxiety in young adults were explored by comparing a quantitative measure of symptoms of anxiety and depression (Achenbach’s YSR and YASR internalising scales) with DSM-IV diagnosed depression and anxiety. 3) The association between family SEP and DSM-IV depression and anxiety was examined in relation to the different pathways to adulthood. 4) Finally, the association between pregnancy loss, abortion and miscarriage, and DSM-IV diagnoses of common psychiatric disorders was assessed in young women who reported early parenting, experiencing a pregnancy loss, or who had never been pregnant. Methods: Data were taken from the Mater University Study of Pregnancy (MUSP), a large birth cohort started in 1981 in Brisbane, Australia. 7223 mothers and their children were assessed five times, at 6 months, 5, 14 and 21 years after birth. Over 3700 young adults, aged 18 to 23 years, were interviewed at the 21-year phase. Respondents completed an extensive series of self-reported questionnaires and a computerised structured psychiatric interview. Three outcomes were assessed at the 21-year phase. Mental health disorders diagnosed by a computerised structured psychiatric interview (CIDI-Auto), the prevalence of DSM-IV depression, anxiety and substance use disorders within the previous 12-month, during the transition (between ages of 18 and 23 years) or lifetime were examined. The primary outcome “current stage in the transition to adulthood” was developed using a measure conceptually constructed from the literature. The measure was based on important demographic markers, and these defined four independent groups: emerging adults (single with no children and living with parents), and three categories of ‘early starter’, singles (with no children or partner, living independently), those with a partner (married or cohabitating but without children) and parents. Early pregnancy loss was assessed using a measure that also defined four independent groups and was based on pregnancy outcomes in the young women This categorised the young women into those who were never pregnant, women who gave birth to a live child, and women who reported some form of pregnancy loss, either an abortion or a spontaneous miscarriage. A series of analyses were undertaken to test the study aims. Potential confounding and mediating factors were prospectively measured between the child’s birth and the 21-year phase. Binomial and multinomial logistic regression was used to estimate the risk of relevant outcomes, and the associations were reported as odds ratios (OR) and 95% confidence intervals (95%CI). Key findings: The thesis makes a number of important contributions to our understanding of the transition to adulthood, particularly in relation to the mental health consequences associated with different pathways. Firstly, findings from the thesis clearly showed that young people who parented or partnered early fared worse across most of the economic and social factors as well as the common mental disorders when compared to emerging adults. That is, young people who became early parents were also more likely to experience recent anxiety (OR=2.0, 95%CI 1.5-2.8) and depression (OR=1.7, 95%CI 1.1-2.7) than were emerging adults after taking into account a range of confounding factors. Singles and those partnering early also had higher rates of lifetime anxiety and depression than emerging adults. Young people who partnered early, but were without children, had decreased odds of recent depression; this may be due to the protective effect of early marriage against depression. It was also found that young people who form families early had an increased risk of cigarette smoking (parents OR=3.7, 95%CI 2.9-4.8) compared to emerging adults, but not heavy alcohol (parents OR=0.4, 95%CI 0.3-0.6) or recent illicit drug use. The high rates of cigarette smoking and tobacco use disorders in ‘early starters’ were explained by common risk factors related to early adversity and lower SEP. Having a child and early marriage may well function as a ‘turning point’ for some young people, it is not clear whether this is due to a conscious decision to disengage from a previous ‘substance using’ lifestyle or simply that they no longer have the time to devote to such activities because of child caring. In relation to the methodological issues associated with assessing common mental disorders in young adults, it was found that although the Achenbach empirical internalising scales successfully predicted both later DSM-IV depression (YSR OR=2.3, 95%CI 1.7-3.1) and concurrently diagnosed depression (YASR OR=6.9, 95%CI 5.0- 9.5) and anxiety (YASR OR=5.1, 95%CI 3.8- 6.7), the scales discriminated poorly between young people with or without DSM-IV diagnosed mood disorder. Sensitivity values (the proportion of true positives) for the internalising scales were surprisingly low. Only a third of young people with current DSM-IV depression (range for each of the scales was between 34% to 42%) were correctly identified as cases by the YASR internalising scales, and only a quarter with current anxiety disorder (range of 23% to 31%) were correctly identified. Also, use of the DSM-oriented scales increased sensitivity only marginally (for depression between 2-8%, and anxiety between 2-6%) above the standard Achenbach scales. This is despite the fact that the DSM-oriented scales were originally developed to overcome the poor prediction of DSM-IV diagnoses by the Achenbach scales. The internalising scales, both standard and DSM-oriented, were much more effective at identifying young people with comorbid depression and anxiety, with OR’s 10.1 to 21.7 depending on the internalising scale used. SEP is an important predictor of both an early transition to adulthood and the experience of anxiety during that time Family income during adolescence was a strong predictor of early parenting and partnering before age 24 but not early independent living. Compared to families in the upper quintile, young people from families with low income were nearly twice as likely to live with a partner and four times more likely to become parents (OR ranged from 2.6 to 4.0). This association remained after adjusting for current employment and education level. Children raised in low income families were 30% more likely to have an anxiety disorder (OR=1.3, 95%CI 0.9-1.9), but not depression, as young adults when compared to children from wealthier families. Emerging adults and ‘early starters’ from low income families did not differ in their likelihood of having a later anxiety disorder. Young women reporting a pregnancy loss had nearly three times the odds of experiencing a lifetime illicit drug disorder (excluding cannabis) [abortion OR=3.6, 95%CI 2.0-6.7 and miscarriage OR=2.6, 95%CI 1.2-5.4]. Abortion was associated with alcohol use disorder (OR=2.1, 95%CI 1.3- 3.5) and 12-month depression (OR=1.9, 95%CI 1.1- 3.1). These finding suggest that the association identified by Fergusson et al between abortion and later psychiatric disorders in young women may be due to pregnancy loss and not to abortion, per se. Conclusion: Findings from this thesis support the view that young people who parent or partner early have a greater burden of depression and anxiety when compared to emerging adults. As well, young women experiencing pregnancy loss, from either abortion or miscarriage, are more likely to experience depression and anxiety than are those who give birth to a live infant or who have never been pregnant. Depression, anxiety and substance use disorders often go unrecognised and untreated in young people; this is especially true in young people from lower SEP. Early identification of these common mental health disorders is important, as depression and anxiety experienced during the transition to adulthood have been found to seriously disrupt an individual’s social, educational and economic prospects in later life.

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Stereo visual odometry has received little investigation in high altitude applications due to the generally poor performance of rigid stereo rigs at extremely small baseline-to-depth ratios. Without additional sensing, metric scale is considered lost and odometry is seen as effective only for monocular perspectives. This paper presents a novel modification to stereo based visual odometry that allows accurate, metric pose estimation from high altitudes, even in the presence of poor calibration and without additional sensor inputs. By relaxing the (typically fixed) stereo transform during bundle adjustment and reducing the dependence on the fixed geometry for triangulation, metrically scaled visual odometry can be obtained in situations where high altitude and structural deformation from vibration would cause traditional algorithms to fail. This is achieved through the use of a novel constrained bundle adjustment routine and accurately scaled pose initializer. We present visual odometry results demonstrating the technique on a short-baseline stereo pair inside a fixed-wing UAV flying at significant height (~30-100m).

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Purpose The neuromuscular mechanisms determining the mechanical behaviour of the knee during landing impact remain poorly understood. It was hypothesised that neuromuscular preparation is subject-specific and ranges along a continuum from passive to active. Methods A group of healthy men (N = 12) stepped-down from a knee-high platform for 60 consecutive trials. Surface EMG of the quadriceps and hamstrings was used to determine pre-impact onset timing, activation amplitude and cocontraction for each trial. Partial least squares regression was used to associate pre-impact preparation with post-impact knee stiffness and coordination. Results The group analysis revealed few significant changes in pre-impact preparation across trial blocks. Single-subject analyses revealed changes in muscle activity that varied in size and direction between individuals. Further, the association between pre-impact preparation and post-impact knee mechanics was subject-specific and ranged along a continuum of strategies. Conclusion The findings suggest that neuromuscular preparation during step landing is subject-specific and its association to post-impact knee mechanics occurs along a continuum, ranging from passive to active control strategies. Further work should examine the implications of these strategies on the distribution of knee forces in-vivo.

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This thesis takes a new data mining approach for analyzing road/crash data by developing models for the whole road network and generating a crash risk profile. Roads with an elevated crash risk due to road surface friction deficit are identified. The regression tree model, predicting road segment crash rate, is applied in a novel deployment coined regression tree extrapolation that produces a skid resistance/crash rate curve. Using extrapolation allows the method to be applied across the network and cope with the high proportion of missing road surface friction values. This risk profiling method can be applied in other domains.

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Aims Physical activity has been shown to increase adolescent self-esteem. The aim of this investigation was to assess adolescent perceptions of parental support for physical activity endeavours, and its relationship with self-esteem among high and low SES groups. Methods Perceptions of parental support, and Rosenberg’s self-esteem (1965) were derived from the Children’s Physical Activity Correlates questionnaire, with scores ranging from 1 (lowest) to 4 (highest). Independent sample t-tests were conducted and Levene’s test indicated homogenous group variance, while Pearson’s r was employed to assess relationships between perceptions of parental support, and self-esteem. Results Overall, 111 (89%) and 64 (55%) high and low SES participants had complete data and were included in the analysis. The high SES differed for self-esteem (M = 3.39, SE = .05) from the low SES group (M = 2.75, SE = .08), t (173) = 6.82, p < .05, with a medium effect size (ES) r = .46. The high SES group scored higher for perceptions of parental support (M = 2.95, SE = .06) than the low SES group (M = 2.71, SE = .07), t (173) = 2.58, p < .05, with a low ES r = .04. Self-esteem was significantly correlated with parental support in both high (r = .34) and low (r = .47) SES groups. Conclusion Results indicate that perceptions of parental support may be a stronger indicator of self-esteem for low, than for high SES adolescents. Future physical activity strategies to promote self-esteem should involve parents as active facilitators.

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Aims Wellness assessments can determine adolescent lifestyle behaviors. A better understanding of wellness differences between high and low SES adolescents could assist policy makers to develop improved strategies to bridge the gap between these two groups. The aim of this investigation was to explore wellness differences between high and low SES adolescents. Methods In total, 241 (125 high and 116 low SES) adolescents completed the 5-Factor Wellness Inventory (5F-Wel). The 5F-Wel comprises 97 items contributing to 17 subscales, 5 dimensions, 4 contexts, total wellness, and a life satisfaction index, with scores ranging from 0-100. Independent sample t-tests were performed with Levene’s test of equality for variances, which checked the assumption of homogeneity of variances. Results Overall, 117 (94%) and 112 (97 %) high and low SES participants had complete data and were included in the analysis. The high SES group scored higher for total wellness (M = 81.09, SE = .61) than the low SES group (M = 75.73, SE = .99). This difference was significant t (186) = 4.635, p < .05, with a medium effect size r = .32. The high SES group scored higher on 23 of 27 scales (21 scales, p < .05), while the low SES group scored higher on the remaining 3 scales (all non-significant). Conclusion These results contribute empirical data to the body of literature, indicating a large wellness discrepancy between high and low SES youth. Deficient areas can be targeted by policymakers to assist in bridging the gap between these groups.

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In situ FT-IR spectroscopy allows the methanol synthesis reaction to be investigated under actual industrial conditions of 503 K and 10 MPa. On Cu/SiO2 catalyst formate species were initially formed which were subsequently hydrogenated to methanol. During the reaction a steady state concentration of formate species persisted on the copper. Additionally, a small quantity of gaseous methane was produced. In contrast, the reaction of CO2 and H2 on ZnO/SiO2 catalyst only resulted in the formation of zinc formate species: no methanol was detected. The interaction of CO2 and H2 with Cu/ZnO/SiO2 catalyst gave formate species on both copper and zinc oxide. Methanol was again formed by the hydrogenation of copper formate species. Steady-state concentrations of copper formate existed under actual industrial reaction conditions, and copper formate is the pivotal intermediate for methanol synthesis. Collation of these results with previous data on copper-based methanol synthesis catalysts allowed the formulation of a reaction mechanism

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Bacterial siderophores may enhance pathogenicity by scavenging iron, but their expression has been proposed to exert a substantial metabolic cost. Here we describe a combined metabolomic-genetic approach to determine how mutations affecting the virulence-associated siderophore yersiniabactin affect the Escherichia coli primary metabolome. Contrary to expectations, we did not find yersiniabactin biosynthesis to correspond to consistent metabolomic shifts. Instead, we found that targeted deletion of ybtU or ybtA, dissimilar genes with similar roles in regulating yersiniabactin expression, were associated with a specific shift in arginine pathway metabolites during growth in minimal media. This interaction was associated with high arginine levels in the model uropathogen Escherichia coli UTI89 compared to its ybtU and ybtA mutants and the K12 strain MG1655, which lacks yersiniabactin-associated genes. Because arginine is not a direct yersiniabactin biosynthetic substrate, these findings show that virulence-associated secondary metabolite systems may shape bacterial primary metabolism independently of substrate consumption

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High power piezoelectric ultrasonic transducers have been widely exploited in a variety of applications. The critical behaviour of a piezoelectric device is encapsulated in its resonant frequencies because of its maximum transmission performance at these frequencies. Therefore power electronic converters should be tuned at those resonant frequencies to transfer electrical power to mechanical power efficiently. However, structural and environmental changes cause variations in the device resonant frequencies which can degrade the system performance. Hence, estimating the device resonant frequencies within the incorporated setup can significantly improve the system performance. This paper proposes an efficient resonant frequency estimation approach to maintain the performance of high power ultrasonic applications using the employed power converter. Experimental validations indicate the effectiveness of the proposed method.

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This study examined the beliefs underlying people’s decision-making, from a theory of planned behaviour (TPB) framework, in the prediction of curbside household waste recycling. Community members in Brisbane, Australia (N = 148) completed a questionnaire assessing the belief based TPB measures of attitudinal beliefs (costs and benefits), normative beliefs (important referents), and control beliefs (barriers) in relation to engaging in curbside household waste recycling for a 2-week period. Two weeks later, participants completed self report measures of recycling behaviour for the previous fortnight. The results revealed that the attitudinal, normative, and control beliefs for people who performed higher and lower levels of recycling differed significantly. A regression analysis identified both normative and control beliefs as the main determinants of recycling behaviour. For normative beliefs, high level recyclers perceived more approval from referents such as partners, friends, and neighbours to recycle all eligible materials. In addition, the strong results for control beliefs indicated that barriers such as forgetfulness, lack of time, and laziness were rated as more likely to hamper optimal recycling performance for low level recyclers. These findings provide important applied information about beliefs to target in the development of future community recycling campaigns.

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Using a Theory of Planned Behavior (TPB) framework the current study explored the beliefs of current blood donors (N=172) about donating during a low and high-risk phase of a potential avian influenza outbreak. While the majority of behavioral, normative, and control beliefs identified in preliminary research differed as a function of donors’ intentions to donate during both phases of an avian influenza outbreak, regression analyses suggested that the targeting of different specific beliefs during each phase of an outbreak would yield most benefit in bolstering donors’ intentions to remain donating. The findings provide insight in how to best motivate donors in different phases of an avian influenza outbreak.