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Deegan B.,Engineering services | Parkin J.,London South Bank University
Proceedings of the Institution of Civil Engineers: Engineering Sustainability | Year: 2011

Developing a network for cycle traffic is a complex process, particularly in a dense and heavily motor trafficked city such as London. The London Cycle Network Plus has delivered cycle routes on strategic highways, and local cycling stakeholders have assisted in the design process through cycle route implementation and stakeholder plans. Stakeholders were trained in aspects of highway engineering and used the London cycling design standards as a reference tool. The paper summarises the lessons learnt, and concludes that knowledge from stakeholders is needed to help in the design process, and such intense involvement was novel in transport planning. The current proposals for cycle superhighways and other borough transport schemes seek to build on previous participative successes and also emphasise planning issues in the geographical neighbourhood of routes. Source

Greenbaum N.,Haifa University | Schwartz U.,Haifa University | Benito G.,CSIC - National Museum of Natural Sciences | Porat N.,Geological Survey of Israel | And 2 more authors.
Quaternary Science Reviews | Year: 2014

The Swakop River is a major ephemeral river (drainage basin area about 30,000km2) crossing the western Namib Desert. Its hydrology and limited water resources depend on storms and floods. Therefore, the hydrology and flow regime in the Swakop River basin determines the availability of water for human use. In this study we present a millennia-long record of extreme floods, using paleoflood hydrological methods and optically stimulated luminescence (OSL) ages. The record includes 44 large floods ranging in date from the late Pleistocene to the present. The oldest six to eight floods are dated from the late Pleistocene to the mid-Holocene (between 14,900±1700 and 5100±620 years ago), with calculated peak discharges of 550-1280m3s-1. Eighteen floods, eleven of which were between 1000 and 1600m3s-1, occurred between 740±90 and 190±10 years ago. Additional 17 later floods occurred between about AD 1850 and 1963, with peak discharges between 100 and 1000m3s-1. The historical record which partly parallels the latter period recorded 17 large floods during the period 1893-1963. Flood frequency analysis (FFA) of the combined systematically gaged record (1963-2003) and the paleoflood record since AD 1270 (740±90 years, the most complete record), was applied using the maximum likelihood method. A two-component extreme value distribution (TCEV) estimates the 1% annual exceedance probability magnitude, using only the systematic gaged record at 520m3s-1. The combined paleoflood, historical, and gage records resulted in a much larger magnitudes for the 1% annual exceedance probability flood magnitude of 1320-1350m3s-1. The 0.1% annual exceedance probability magnitude is estimated at 770m3s-1 and 2100-2150m3s-1, respectively.The hydroclimatic interpretation of this paleoflood record is complex, due to the discontinuity of the record. During the late Holocene, our flood data show three intervals differing in their flood regime: (1) 1280±80 to 740±90 years BP, with one extraordinary flood (>200m3s-1) about every 180 years; (2) 740±90 to 200±45 14C years BP, with one large flood per 80 years; and (3) 200±45 14C years BP to AD1963, with one large flood per 7 years. Interval 2 represents large floods, probably related to the transition from a drier climate to the colder and probably wetter climate of the Little Ice Age (LIA). The third period relates to the end of the LIA and to a wetter period of the 19th and early 20th centuries in which more rainfall in the Kalahari and Namib Deserts and many historical floods were documented.The presence of three distinct calcretes rich in calcified rhizoliths at one of the sites, two of which were dated by OSL to 13.2±1.9ka and 8.8±1.0ka, indicates, at least locally, higher moisture availability than in the current semiarid climate; the presence of denser vegetation can be associated with increased groundwater seepage and wetter climatic conditions. © 2014 Elsevier Ltd. Source

Shaeri S.,Griffith University | Tomlinson R.B.,Griffith University | Etemad-Shahidi A.,Griffith University | Strauss D.,Griffith University | Hunt S.,Engineering services
Journal of Coastal Research | Year: 2013

Currumbin Creek is a small tidal inlet in south-eastern Queensland, Australia. There is a long history of morphological changes, entrance stabilization works and maintenance dredging activities. Despite these activities an effective longterm management plan is yet to be implemented. A key component of the development of such a plan is a model of morphological change, and this paper addresses an investigation of the dynamics of the whole system. A field campaign carried out in March, 2011 and included measurement of nearshore wave regimes, tidal levels and currents inside the creek, and also drogue tracking in the inlet entrance. Wave data was collected over six weeks by ADCPs in water depth of about 7-8 m. Tidal current discharges were also measured by an ADCP over two tidal cycles of 14.4 (spring) and 15 (neap) hours. Water levels were recorded using a Valeport Water Level Recorder during the whole measuring period. The investigations show that the creek is mixed, but mostly flood dominated and therefore, there is a reasonable potential for sediment to rapidly infill the entrance and for the entrance to be dominated by natural bypassing. This study is part of a broader research project aiming to maintain longer, more durable and stable tidal-inlet entrance channels in Currumbin Creek. These findings will contribute to the design of alternative entrance geometry or maintenance strategies in the next phase. © Coastal Education & Research Foundation 2013. Source

Silleto M.N.,Engineering services | Yoon S.-J.,Kyushu University | Arakawa K.,Kyushu University
International Journal of Energy Research | Year: 2015

Piezoelectric cable is a commercial electronic sensor that incorporates the piezoelectric polymer polyvinylidene fluoride. This paper investigated a potential application of piezoelectric cable for energy harvesting. A method for testing the electrical output using the tensile load was developed and used to determine the output properties of the cable. A design for a piezoelectric cable fiber composite is presented, along with recommendations for potential applications and further research. © 2014 John Wiley & Sons, Ltd. Source

Rudolf A.,ILF Consulting Engineers AG | Kienzler T.,Engineering services
Underground - The Way to the Future: Proceedings of the World Tunnel Congress, WTC 2013 | Year: 2013

The meteorological pressure difference between tunnel portals is an important parameter for ventilation designs. If tunnel portals are not too far away, it is possible to measure the pressure difference directly. However, with augmenting tunnel length, the use of pressure tubes and a differential pressure measurement becomes increasingly difficult, because the influence of the local variations of the air inside the tunnel on the measured overall pressure difference is difficult to compensate. In these cases, it is necessary to measure the absolute pressures at the portals with a precision sufficient to provide useful pressure differences for the ventilation design. The present paper describes a measurement installation which has been used in the longest tunnel with directional traffic in Switzerland, the 9.2 km long Seelisbergtunnel. In this project, the required precision of the measured pressure difference was 10 Pa as this was the preliminary estimated value. The present paper informs about the technique used, the problems encountered and the results. © 2013 Taylor & Francis Group. Source

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