Application of optimization techniques to vehicle design: A review

The work that has been done in the last decade or so in the application of optimization techniques to vehicle design is discussed. Much of the work reviewed deals with the design of body or suspension (chassis) components for reduced weight. Also reviewed are studies dealing with system optimization problems for improved functional performance, such as ride or handling. In reviewing the work on the use of optimization techniques, one notes the transition from the rare mention of the methods in the 70's to an increased effort in the early 80's. Efficient and convenient optimization and analysis tools still need to be developed so that they can be regularly applied in the early design stage of the vehicle development cycle to be most effective. Based on the reported applications, an attempt is made to assess the potential for automotive application of optimization techniques. The major issue involved remains the creation of quantifiable means of analysis to be used in vehicle design. The conventional process of vehicle design still contains much experience-based input because it has not yet proven possible to quantify all important constraints. This restraint on the part of the analysis will continue to be a major limiting factor in application of optimization to vehicle design

The Stratigraphic Record of Pre-breakup Geodynamics: Evidence from the Barrow Delta, offshore Northwest Australia

The structural and stratigraphic evolution of rift basins and passive margins has been widely studied, with many analyses demonstrating that delta systems can provide important records of post-rift geodynamic processes. However, the apparent lack of ancient syn-breakup delta systems and the paucity of seismic imaging across continent-ocean boundaries means the transition from continental rifting to oceanic spreading remains poorly understood. The Early Cretaceous Barrow Group of the North Carnarvon Basin, offshore NW Australia was a major deltaic system that formed during the latter stages of continental rifting, and represents a rich sedimentary archive, documenting uplift, subsidence and erosion of the margin. We use a regional database of 2D and 3D seismic and well data to constrain the internal architecture of the Barrow Group. Our results highlight three major depocentres: the Exmouth and Barrow sub-basins, and southern Exmouth Plateau. Over-compaction of pre-Cretaceous sedimentary rocks in the South Carnarvon Basin, and pervasive reworking of Permian and Triassic palynomorphs in the offshore Barrow Group, suggests that the onshore South Carnarvon Basin originally contained a thicker sedimentary succession, which was uplifted and eroded prior to breakup. Backstripping of sedimentary successions encountered in wells in the Exmouth Plateau depocentre indicate anomalously rapid tectonic subsidence (≤0.24 mm yr-1) accommodated Barrow Group deposition, despite evidence for minimal, contemporaneous upper crustal extension. Our results suggest that classic models of uniform extension cannot account for the observations of uplift and subsidence in the North Carnarvon Basin, and may indicate a period of depth-dependent extension or dynamic topography preceding breakup

An Extension of Dematerialization Theory: Incorporation of Technical Performance Increases and the Rebound Effect

Dematerialization is the reduction in the quantity of materials needed to produce something useful over time. Dematerialization fundamentally derives from ongoing increases in technical performance but it can be counteracted by demand rebound -increases in usage because of increased value (or decreased cost) that also results from increasing technical performance. A major question then is to what extent technological performance improvement can offset and is offsetting continuously increasing economic consumption. This paper contributes to answering this question by offering some simple quantitative extensions to the theory of dematerialization. An inequality criterion for dematerialization is developed that includes technical performance changes over time and demand rebound effects: the inequality highlights the importance of demand elasticity and the annual technical performance improvement rate. The paper then empirically examines the materials consumption trends as well as cost trends for a large set of materials and a few modern artifacts over the past decades. In all 57 cases examined, the particular combinations of demand elasticity and technical capability rate improvement for each case are consistent with continuation of materialization. Overall, the theory extension and empirical examination indicate that dematerialization and sustainability are significant challenges not easily met by undirected technological change

Why caregivers of people with dementia don\u27t utilise out-of-home respite services

Carers of people with dementia consistently report an unmet need for respite. Despite this, the overall proportion of carers who utilise available day centre, in-home and residential respite programs tends to be low and, even then, use is often delayed and only at very low intensities. In order to support carers in appropriate and supportive use of respite services, program planners and service providers need a good understanding of the factors influencing use and non-use of respite services. With this in mind, a community based survey of 152 help-seeking caregivers of people with dementia (NSW, Australia) was undertaken to establish what variables make the use of use of day, in-home and residential respite services difficult for caregivers. Results from multivariate logistic regression of survey data reveal that factors such as refusal of the person with dementia to attend services, and low perceived utility of services for the care recipient with dementia, are significantly correlated with caregivers not utilising available services for respite. Such results highlight that whilst the focus of respite services has legitimately emphasised the needs of caregivers for a break, low utilisation of services is likely to persist unless caregivers believe that service use will also be acceptable and of benefit to the person with dementia to whom they provide care

Dyke architecture, mineral layering, and magmatic convection; new perspectives from the Younger Giant Dyke Complex, S Greenland

The expedition was funded by the Mining Institute of Scotland Trust, the Institute of Materials, Minerals and Mining, the Society of Economic Geologists Hickok-Radford Fund, the Edinburgh Geological Society, the Augustine Courtauld trust and the Scott Polar Research Institute.Igneous sheet intrusions are a fundamental component of volcano plumbing systems. Identifying how sheet intrusion emplacement and geometry controls later magmatic processes is critical to understanding the distribution of volcanic eruptions and magma-related ore deposits. Using the Younger Giant Dyke Complex, a Mesoproterozoic suite of large (< 800 m wide) mafic dykes in southern Greenland, we assess the influence sheet of emplacement and geometry on subsequent magma flow and mush evolution. Through structural mapping, petrographic observations, and anisotropy of magnetic susceptibility fabric analyses, we show that the Younger Giant Dyke Complex was emplaced as a series of individual dyke segments, which following coalescence into a sheet intrusion remained largely isolated during their magmatic evolution. Through petrographic evidence for liquid-rich growth of cumulus phases, concentric magnetic fabrics, and the detailed study layered zones within the Younger Giant Dyke Complex, we infer magma convection occurred within the cores of each dyke element. We particularly relate layering to hydrodynamic sorting processes at a magma-mush boundary towards the base of each convection cell. Overall, our work demonstrates that the initial geometry of sheet intrusions can constrain magma flow patterns and affect the distribution of crystallisation regimes.Publisher PDFPeer reviewe

The Volatile Composition of the Split Ecliptic comet 73P/Schwassmann-Wachmann 3: A Comparison of Fragments C and B

The composition of fragments C and B of the Jupiter-family comet 73P/Schwassmann-Wachmann 3 (SW3) was investigated in early April of 2006 at IR wavelengths using high-dispersion echelle spectroscopy. Both fragments were depleted in ethane, and C was depleted in most forms of volatile carbon. In particular, fragment C shows a severe depletion of CH_(3)OH but a "normal" abundance of HCN (which has a similar volatility). Thermal processing is a possible explanation, but since fragment B is perhaps sublimating fresher material because of the frequent outbursts and fragmentation, the observed depletions might have cosmogonic implications. The chemistry of the volatile ices in SW3, like in the Oort Cloud comet C/1999 S4 (LINEAR), may be associated with sublimation of icy mantles from precometary grains followed by subsequent gas-phase chemistry and recondensation

Sugar and artificially sweetened beverage consumption and adiposity changes: National longitudinal study

BACKGROUND: In response to increasing policy action and public concern about the negative health effects of sugar-sweetened beverages (SSBs), there is increased promotion of artificially sweetened beverages (ASBs). These have been linked with obesity and diabetes in recent experimental work. This study examined associations between SSB and ASB consumption and changes in adiposity in a nationally representative sample of UK children. METHODS: We conducted a longitudinal study of 13,170 children aged 7–11 years in the UK Millennium Cohort Study, collected in 2008 and 2012. Logistic regression was used to assess socio-demographic and behavioural correlates of weekly SSB and ASB consumption at 11 years. Linear regression examined associations between SSB/ASB consumption and changes in adiposity measures between 7 and 11 years. RESULTS: Boys were more likely to consume SSBs weekly (62.3 % v 59.1 %) than girls at age 11 years. South Asian children were more likely to consume SSBs weekly (78.8 % v 58.4 %) but less likely to consume ASBsweekly (51.7 % v 66.3 %) than White children. Daily SSB consumption was associated with increases in percentage body fat between ages 7 and 11 (+0.57 %, 95 % confidence intervals 0.30;0.83). Daily ASB consumption was associated with increased percentage body fat at age 11 (+1.18 kg/m(2), 0.81;1.54) and greater increases between ages 7 and 11 (+0.35 kg/m(2), 0.09;0.61). CONCLUSION: Consumption of SSBs and ASBs was associated with BMI and percentage body fat increases in UK children. Obesity prevention strategies which encourage the substitution of SSBs with ASBs may not yield the adiposity benefits originally intended and this area should be a focus for further research

Pediatric Transplantation in the United States, 1996–2005

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73448/1/j.1600-6143.2007.01780.x.pd