Introducing Originality and Innovation in Engineering Teaching: The Hydraulic Design of Culverts

Recently the teaching of engineering design has become a presentation of standards and codes rather than the learning of sound design practices. Too many students request formulae and equations to solve a design exercise and they fail to develop any design originality. The present student attitude leads to young graduate engineers without critical ability and innovative flair. The writer has developed an innovative hydraulic design exercise based upon culvert design. Each design exercise could lead to more than one correct design per student in the class. Students have to learn basic design calculations based upon lecture material, notes, field visits and laboratory experiment. The practical component (laboratory, field visit) contributes significantly to their understanding of the complete system, including some basic safety and professional issues

Unsteady Two-Dimensional Orifice Flow: A Large-Size Experimental Investigation

Orifice flows were used as water clocks since the Antiquity up to the 16-th century. Today orifices and nozzles are used for measuring discharges. Most works were conducted with steady flow conditions and there is little information on the unsteady flow pattern. In this study, the writers describe an experimental investigation of an unsteady orifice flow discharging vertically. The study was conducted in a large-size facility with a rectangular orifice (0.75-m by 0.07-m) discharging up to 1.2 m3 in about 10 seconds. The study presents new information on the unsteady flow patterns, the discharge capacity and the velocity field in the reservoir. The results are compared with 'classical' orifice flow results

Hydraulic Performances of Minimum Energy Loss Culverts in Australia

Culverts are among the most common hydraulic structures. Modern designs do not differ from ancient structures and are often characterised by significant afflux at design flows. A significant advance was the development of the Minimum Energy Loss (MEL) culverts in the late 1950s. The design technique allows a drastic reduction in upstream flooding associated with lower costs. The development and operational performances of this type of structure is presented. The successful operation of MEL culverts for more than 40 years is documented with first-hand records during and after floods. The experiences demonstrate the design soundness while highlighting the importance of the hydraulic expertise of the design engineers

Patterns in Greater Sage-grouse population dynamics correspond with public grazing records at broad scales

Human land use, such as livestock grazing, can have profound yet varied effects on wildlife interacting within common ecosystems, yet our understanding of land-use effects is often generalized from short-term, local studies that may not correspond with trends at broader scales. Here we used public land records to characterize livestock grazing across Wyoming, USA, and we used Greater Sage-grouse (Centrocercus urophasianus) as a model organism to evaluate responses to livestock management. With annual counts of male Sage-grouse from 743 leks (breeding display sites) during 2004-2014, we modeled population trends in response to grazing level (represented by a relative grazing index) and timing across a gradient in vegetation productivity as measured by the Normalized Vegetation Difference Index (NDVI). We found grazing can have both positive and negative effects on Sage-grouse populations depending on the timing and level of grazing. Sage-grouse populations responded positively to higher grazing levels after peak vegetation productivity, but populations declined when similar grazing levels occurred earlier, likely reflecting the sensitivity of cool-season grasses to grazing during peak growth periods. We also found support for the hypothesis that effects of grazing management vary with local vegetation productivity. These results illustrate the importance of broad-scale analyses by revealing patterns in Sage-grouse population trends that may not be inferred from studies at finer scales, and could inform sustainable grazing management in these ecosystems

Leadership and the Australian Greens

This paper examines the inherent tension between a Green political party’s genesis and official ideology and the conventional forms and practices of party leadership enacted in the vast bulk of other parties, regardless of their place on the ideological spectrum. A rich picture is painted of this ongoing struggle through a case study of the Australian Greens with vivid descriptions presented on organisational leadership issues by Australian state and federal Green members of parliaments. What emerges from the data is the Australian Green MPs’ conundrum in retaining an egalitarian and participatory democracy ethos while seeking to expand their existing frame of leadership to being both more pragmatic and oriented towards active involvement in government