Obituary: Alan Grahame Lloyd (1926-1999)

Teaching/Communication/Extension/Profession,

An experience of modularity through design

We aim to utilise the experiences of a marine industry-based design team to determine the need for research into a modular design methodology in an industrial environment. In order to achieve this we couple the outcome of a current design project with the findings of a recent literature survey with the objectives of firstly, clarifying why a methodology is required and, secondly, defining the key elements which the methodology would have to realise or address. The potential benefits of modularity have long been recognised in the shipbuilding industry. Many shipbuilders adopt a 'module' approach to ship construction whereby the ship structure is separated into a number of large structural 'blocks' to ease manufacture and manoeuvrability during construction. However, as understanding of the capabilities of modularity as a design tool develops there is increased interest in capitalising on the differing life phase benefits of modularity such as reduced design costs and time, increased ease of maintenance, upgrade, re-use, redesign and standardisation across individual products and product families. This is especially pertinent in naval shipbuilding where the maintenance of a class of ship requires that all previously designed ships in that class must be of similar outfitting and must be able to interface with the new ship, in terms of propulsion, weapons, communications and electronics, and thus often require some form of retrofit. Therefore, many shipbuilders are moving from viewing modularity as a purely 'manufacturing' principle to a design centred principle. However, as noted by Chang and Ward 'none of the design theories or tools in the mechanical world serves as an articulate procedure for designers to follow in practising modular design'. Thus, despite the identification of a need to introduce modular principles at an earlier stage than detail design and construction, there is little aid in the form of tools, techniques and methodologies for designers in practice

Planning and the public : actor-networks and the plan-making process.

This study explores the development plan-making process in two local authorities, and focuses on the role different groups, including 'the public', play in this. This research aims to uncover the ways in which the practices of plan making are constructed through the work of actors and texts, and to trace how these actions reflect and constitute relations of power. Plans have been viewed as modernist tools. However this conception has been criticised in work drawing on the writings of Habermas and Foucault, which will be critically assessed. Problems associated with these theories and a need to trace how actions and structures might be constituted led to adopting a theoretical framework drawing on actor-network theory. This theory has a radical view of structure, agency and power and forces attention onto how stabilities are constructed. The theoretical framework adopted draws on these concerns to trace how actors, entities and networks emerge through social actions. The research questions focus these concerns onto understanding how plans are written, who is important in this and how entities such as 'local authorities' and 'the public' are constructed. Qualitative research was carried out in two cases, examining how the plans were written and focusing on how techniques of involving 'the public' were constructed. Case study descriptions trace how networks were built and how were important in mediating actions. In particular, the ways in which 'councils' 'officers', 'members', 'the public' and 'central government' are defined, form a focus. Analysis of the two cases revealed significant similarities attributed to a 'central government' network. Differences arose in the ways in which 'council' networks composed different practices of plan-writing and how officers and members were defined. This study shows how texts and actors shape plan-making, and how certain practices of governance are constructed

Photoelectron spectroscopy as a probe of intramolecular vibrational dynamics in electronically excited toluene

Intramolecular vibrational energy redistribution (IVR) is a commonly-observed phenomenon whereby vibrational energy can be transferred between different parts of a polyatomic molecule. This process has profound implications for the understanding of chemical reactivity. In this work, IVR is studied in the S1 electronic state of toluene using time-resolved and frequency-resolved techniques. Both experiments are based upon laser photoelectron spectroscopy in the collision-free environment of a molecular beam. The time-resolved experiments employ laser pulses of ~1 ps duration and ~15 cm^-1 bandwidth. In a pump-probe scheme, the molecule is first excited to a chosen superposition of vibrational states in the S1 manifold and then ionised by a second photon. The photoelectrons produced by the probe laser pulse are detected using velocity map imaging in order to obtain a vibrationally resolved photoelectron spectrum. Changes in the spectrum as a function of time give a direct view of the evolution of the vibrational state. The use of a two-colour ionisation scheme substantially improves the resolution compared with previous work. High resolution zero kinetic energy (ZEKE) photoelectron spectra have also been obtained for the first time from excited vibrational levels in the S1 electronic state of toluene. These experiments employed laser pulses of ~5 ns duration and ~0.3 cm^-1 bandwidth, allowing the excitation of individual S1 vibrational levels rather than a superposition. The nanosecond and picosecond experiments therefore give complementary information. A Fermi resonance at ~460 cm^-1 above the S1 origin in toluene is shown to be more complicated than previously thought, and provides the first demonstration of the use of time-resolved photoelectron spectroscopy to gain quantitative measurements of vibrational coupling matrix elements. Lifetimes of dissipative IVR have been determined following the preparation of high-frequency vibrations, and at intermediate energies several "doorway states" which mediate the IVR mechanism have been identified for the first time

A review of the fluvial geomorphology monitoring of the receiving streams of the Mooi-Mgeni [River] Transfer Scheme Phase 1.

Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.The Mgeni River is the major water resource for the eThekwini Metropolitan and Msunduzi Municipalities. At the end of 2002, the Mooi-Mgeni Transfer Scheme Phase 1, which transfers water from the Mooi River into the Mgeni catchment to augment the water supply to this region, was completed. The interbasin transfer of water resulted in the loss of habitat, erosion of the stream channel and transformation of the riparian zone in the receiving streams. Stream regulation resulting in an altered flow regime is considered the greatest threat to a riverine environment. An Environmental Management Plan (EMP), incorporating fluvial geomorphological monitoring procedures, was implemented to monitor the impact of the transfer on the receiving streams, the Mpofana and Lions Rivers, and to determine the rate and magnitude of erosion. A comparison of the geomorphological monitoring procedure of the EMP with best practice geomorphological monitoring derived from a review of the national and international stream geomorphological literature was conducted in this study. In addition, the implementation of the EMP geomorphological monitoring procedures was described and onsite observations of physical impacts on the receiving streams were completed. The geomorphological monitoring of the EMP included the use of erosion pins, survey of stream cross-sections and fixed-point photography. Photographs and data were collected from February 2003 to June 2006. The comparison of these monitoring methods against stream assessment best practices revealed the strengths and weaknesses of the geomorphological monitoring implemented in the receiving streams. Several key weaknesses were revealed. Firstly, an inadequate number of stream cross sections was included in the monitoring procedures. Secondly, although the erosion pins indicated some general trends in the erosion of the stream channel, they did not give a true impression of the rate and magnitude of change in slope and channel width of the stream, and the location of the erosion pins sites did not take into account the actual direction of flow during transfer as erosion pin sites were selected during low flow conditions. In addition, it was difficult to determine whether the erosion pins had been lost due to erosion or to turbulence. The results were difficult to assess and did not show whether the erosion was localised at the pins or the section of bank or stream profile. Thirdly, analysis of platform changes in the stream channel (e.g. through a comparison of aerial photograph sets) was lacking and no attempt was made to integrate the results from the different methods. Overall, the study concluded that the geomorphological monitoring of the EMP was limited, and it did not highlight the rate and magnitude of erosion in the receiving streams. Based on the findings of this study, recommendations are provided for geomorphological monitoring of the receiving streams of the Mooi Mgeni Transfer Scheme

Laboratory and field partial discharge measurement in HVDC power cables

A range of experimental and field measurements of partial discharge (PD) activity under high voltage direct current (HVDC) conditions have been conducted with the goal of developing effective monitoring techniques for PD in HVDC cables and ancillary equipment, particularly in offshore renewable energy HVDC grid installations. Laboratory measurements on insulation test objects and cross linked polyethylene (XLPE) cable samples have been conducted to better understand the characteristics of PD activity under direct current (DC) stress in comparison with AC. In addition, long-term PD measurements carried out at both an HVDC cable aging laboratory and an in-service HVDC interconnector circuit are presented together with a description of the monitoring system architecture