Research on optimization-based design

Research on optimization-based design is discussed. Illustrative examples are given for cases involving continuous optimization with discrete variables and optimization with tolerances. Approximation of computationally expensive and noisy functions, electromechanical actuator/control system design using decomposition and application of knowledge-based systems and optimization for the design of a valve anti-cavitation device are among the topics covered

Effect of flower shapes and nectar guides on the behaviour of foraging honeybees

RESP-632

Factors associated with pregnancy and STI among Aboriginal students in British Columbia.

BACKGROUND: Aboriginal adolescents are more likely to become pregnant and contract an STI than other Canadian adolescents. This study provides some of the first data on factors associated with these outcomes among Aboriginal adolescents. METHODS: A secondary analysis was conducted using 2003 data from a large cross-sectional survey of British Columbia secondary school students. 445 young women and 360 young men who identified as Aboriginal and reported ever having sex were included in analyses. Associations between self-reported pregnancy and STI and 11 exposure variables were examined using logistic regression. RESULTS: Of young women, 10.6% reported a pregnancy; 10.5% of young men reported causing a pregnancy. An STI diagnosis was reported by 4.2% of young women and 3.9% of young men. In multivariate analyses for young men, ever having been sexually abused was the strongest consistent risk factor for causing a pregnancy (AOR = 4.30, 95% CI 1.64-11.25) and STI diagnosis (AOR = 5.58, 95% CI 1.61-19.37). For young women, abuse was associated with increased odds of pregnancy (AOR = 10.37, 95% CI 4.04-26.60) but not STI. Among young women, substance use was the strongest consistent risk factor for both pregnancy (AOR = 3.36, 95% CI 1.25-9.08) and STI (AOR = 5.27, 95% CI 1.50-18.42); for young men, substance use was associated with higher odds of STI (AOR = 4.60, 95% CI 1.11-19.14). Factors associated with decreased risk included community, school and family involvement. CONCLUSIONS: Health care professionals, communities and policy-makers must urgently address sexual abuse and substance use. Exploring promotion of school and community involvement and family cohesion may be useful for sexual health interventions with Aboriginal students

The behaviour of robber honeybees

RESP-339

Quantifying Channel Responses to the Removal of the Glines Canyon Dam in the Middle Reach of the Elwha River, Washington

Four different study sites throughout the middle reach of the Elwha River were monitored before, during, and after the dam removal process over a period of two years from 2012-2014. The complexity of the river geometry was a major factor in the ability of the river to trap and accumulate the new influx of woody debris and sediment from the dam removal, which influenced the response of the river channel. The change that occurred was quantified by using repeat Terrestrial LiDAR (TLS), sediment distribution surveys, and large woody debris mapping techniques. The morphologic changes that occurred during this time were caused by multiple different geomorphic influences. The most notable was the initial sediment pulse that that inundated the downstream river channel in the first few months of the reservoir sediment release. In turn, it filled the riffles and pools throughout the entire middle reach of the river, and the subsequent deposition was channel geometry dependent. As the initial sediment wave dissipated and the river continued transport sediment from the Glines Canyon Dam, the channel geometry was still the major factor in woody debris collection and sediment deposition followed by river discharge. Woody debris anchored and accumulated on sediment bars throughout the entire middle reach; it became apparent that the more complex the channel system (i.e. multiple channels, vegetated islands, riffles and pools, or a sharp channel bend), the more likely the woody debris was to collect. Furthermore, as the woody debris deposited coalesced into log jams, it influenced the sediment deposition by armoring the banks of channels and creating areas of slow moving water. The combined deposition of sediment and woody debris caused areas of the channel to migrate, increasing the complexity of the river geometry. This study has provided some much-needed empirical data necessary to model future dam removal projects. It demonstrated that the use of TLS combined with surveys of large woody debris and sediment distribution can provide detailed information about the effects of the dam removal in different geomorphic settings

Stimuli Eliciting Mating Behaviour of Bumblebee (Bomb Us Pratoruml.) Males

RESP-647

Preliminary investigations on the occupation of artificial nests by Osmia rufa L.(Hymenoptera, Megachilidae)

RESP-631