Aeration Effects on Impact: Drop Test of a Flat Plate

Verbatim reproduction or republication of the papers or articles or part of the articles (e.g., figures or tables) by their authors, after the publication or presentation at the ISOPE meetings and journal, is permitted by the International Society of Offshore and Polar Engineers (ISOPE), provided the full credit is given to the authors, to the publisher, The International Society of Offshore and Polar Engineers (ISOPE), and to the Conference, Symposium or Journal - more specifically not to remove the copyright imprint on page 1 of the paper. The permission does not extend to copying for resale and to re-copyrighting the whole or part of the papers. Posting on your organization's website of the paper(s) you specified is allowed only where only your organization's employees including the students can view free of charge the paper authored or co-authored by your organization's employees, and www.isope.org is provided for the paper(s) in the ISOPE proceedings or journals. Regards, Prof. Jin S Chung Executive Director isope, 495 North Whisman Road, Suite 300 Mountain View, California 94043-5711, USA T 1-650-254-1871; F 1-650-254-2038; [email protected] [email protected], www.isope.org www.deepoceanmining.orgAeration effects on impact have been investigated by dropping a flat plate onto the water surface, in which the water is aerated to various degrees. An experimental study has been carried out in the newly commissioned Ocean Basin at Plymouth University’s COAST Lab. The falling block comprises a rigid impact plate connected to two driver plates and its total mass can be varied between 32 kg and 52 kg. The impact plate is 0.25m long, 0.25 m wide and 0.012 m high. The impact velocity is varied between 4 m/s and 7 m/s. Preliminary results of the impact tests are presented here. Visualised results show that there are significant differences between jet formation after impact of the plate in pure water and in aerated water. There is significant reduction of the maximum pressures from those measured in pure water to those measured in aerated water

A solution to the mu problem in the presence of a heavy gluino LSP

In this paper we present a solution to the $\mu$ problem in an SO(10) supersymmetric grand unified model with gauge mediated and D-term supersymmetry breaking. A Peccei-Quinn symmetry is broken at the messenger scale $M\sim 10^{12}$ GeV and enables the generation of the $\mu$ term. The boundary conditions defined at $M$ lead to a phenomenologically acceptable version of the minimal supersymmetric standard model with novel particle phenomenology. Either the gluino or the gravitino is the lightest supersymmetric particle (LSP). If the gravitino is the LSP, then the gluino is the next-to-LSP (NLSP) with a lifetime on the order of one month or longer. In either case this heavy gluino, with mass in the range 25 - 35 GeV, can be treated as a stable particle with respect to experiments at high energy accelerators. Given the extensive phenomenological constraints we show that the model can only survive in a narrow region of parameter space resulting in a light neutral Higgs with mass $\sim 86 - 91$ GeV and $\tan\beta \sim 9 - 14$. In addition the lightest stop and neutralino have mass $\sim 100 - 122$ GeV and $\sim 50 - 72$ GeV, respectively. Thus the model will soon be tested. Finally, the invisible axion resulting from PQ symmetry breaking is a cold dark matter candidate.Comment: 30 pages, 9 figure

Heterotic Cosmic Strings

We show that all three conditions for the cosmological relevance of heterotic cosmic strings, the right tension, stability and a production mechanism at the end of inflation, can be met in the strongly coupled M-theory regime. Whereas cosmic strings generated from weakly coupled heterotic strings have the well known problems posed by Witten in 1985, we show that strings arising from M5-branes wrapped around 4-cycles (divisors) of a Calabi-Yau in heterotic M-theory compactifications, solve these problems in an elegant fashion.Comment: 25 pages, v2: section and references adde

Modal testing of offshore rock lighthouses around the British Isles

EURODYN 2017, 2017-09-10, 2017-09-13, RomeThis is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Given that 95 per cent of the UK’s international trade is transported by sea, and as a vital complement to fallible virtual navigational aids such as GPS, rock-mounted lighthouses constructed in the 19th century have a crucial role to play in safe navigation. However the longevity of these historical structures is threatened by extreme weather so in the UK, the General Lighthouse Authorities comprising Trinity House, the Northern Lighthouse Board and the Commissioners of Irish Lights are supporting three British universities in a program of linked experimental and analytical investigations of full-scale performance under extreme wave loading. The aim is to use structural models calibrated by modal testing to deduce wave loading from response recorded by long-term monitoring. The paper describes the procedures for modal testing, taking into account the constraints on access, logistics, unfamiliar layout and time. The test program sequentially covered Les Hanois, Wolf Rock, Longships and Bishops Rock lighthouses over summer 2016 followed by Fastnet Rock in December 2016. Some conventional techniques of forced and ambient vibration testing were used along with some unusual excitation methods. Results from the measurements and observations on the particular challenges associated with testing two of these iconic structures are presented.The research was funded by EPSRC grant EP/N022955/

Alternate route to tax equity

Illustration not included in Web versio

Enacting Productive Dialogue: Addressing the Challenge that Non-Human Cognition Poses to Collaborations Between Enactivism and Heideggerian Phenomenology

This chapter uses one particular proposal for interdisciplinary collaboration – in this case, between early Heideggerian phenomenology and enactivist cognitive science – as an example of how such partnerships may confront and negotiate tensions between the perspectives they bring together. The discussion begins by summarising some of the intersections that render Heideggerian and enactivist thought promising interlocutors for each other. It then moves on to explore how Heideggerian enactivism could respond to the challenge of reconciling the significant differences in the ways that each discourse seeks to apply the structures it claims to uncover

Implications of the 2011 Great East Japan Tsunami on sea defence design

After the 2004 Boxing Day tsunami, much of the world's effort to defend against tsunami concentrated on tsunami warning and evacuation. The 2011 Great East Japan Earthquake and Tsunami led to direct and indirect losses as well as the deaths of many vulnerable members of Japan's coastal communities. This event has resulted in Japan rethinking and revising its design codes for sea defence structures. The new guidance emerging from this process is a valuable resource for other countries re-evaluating their own current mitigation strategies and this paper presents details of this process. The paper starts with the history of sea defence design standards in Japan and explains the process of revision of design guidelines since 2011. Examples of sea defences that failed and have since been rebuilt, observed during the two Earthquake Engineering Field Investigation Team (EEFIT) missions of 2011 and 2013, are also presented. The paper concludes with a discussion of international approaches and their application to nuclear power stations in Japan and the UK