Design reuse research : a computational perspective

This paper gives an overview of some computer based systems that focus on supporting engineering design reuse. Design reuse is considered here to reflect the utilisation of any knowledge gained from a design activity and not just past designs of artefacts. A design reuse process model, containing three main processes and six knowledge components, is used as a basis to identify the main areas of contribution from the systems. From this it can be concluded that while reuse libraries and design by reuse has received most attention, design for reuse, domain exploration and five of the other knowledge components lack research effort

Pray for the People Who Feed You : Voices of Pauper Children in the Industrial Age

Following the Industrial Revolution in the late nineteenth and early twentieth centuries, countries such as the United States and England experienced a widening gap between the rich industrialists and the impoverished working class. As a result, poverty quickly shifted from a localized problem to a national epidemic. Each country was faced with the challenges of addressing and alleviating poverty on a national scale. With a limited amount of resources, questions arose about who should receive relief. What should it look like? How should it be administered? And how would poverty and policy affect political, economic, social and familial structures? [excerpt]https://cupola.gettysburg.edu/artcatalogs/1016/thumbnail.jp

Modularity in support of design for re-use

We explore the structuring principle of modularity with the objective of analysing its current ability to meet the requirements of a 're-use' centred approach to design. We aim to highlight the correlation's between modular design and 're-use', and argue that it has the potential to aid the little-supported process of 'design-for-re-use'. In fulfilment of this objective we not only identify the requirements of 'design-for-re-use', but also propose how modular design principles can be extended to support 'design-for-re-use'

Re-using knowledge : why, what and where

Previously the 're-use' focus has centred on specific and/or standard parts, more recently however, [standard components] are being developed...to enable both the re-use of the part and the experience associated with that part'. This notion is further extended by Finger who states that 'designers may re-use a prior design in it's entirety,...may re-use an existing shape for a different function, or may re-use a feature from another design'. Reinforcing this notion we currently consider re-use to reflect the utilisation of any knowledge gained from a design activity and not just past designs of artefacts. Our research concerns the improvement of formal 're-use' support and as such we have identified a need to gain a better understanding of how design knowledge can be utilised to support 're-use'. Thus, we discuss the requirements of successful 're-use' and attempt to ascertain within this skeleton: what knowledge can be re-used; how to maximise its' applicability; and where and when it can be utilised in new design

Gravity-driven draining of a thin rivulet with constant width down a slowly varying substrate

The locally unidirectional gravity-driven draining of a thin rivulet with constant width but slowly varying contact angle down a slowly varying substrate is considered. Specifically, the flow of a rivulet in the azimuthal direction from the top to the bottom of a large horizontal cylinder is investigated. In particular, it is shown that, despite behaving the same locally, this flow has qualitatively different global behaviour from that of a rivulet with constant contact angle but slowly varying width. For example, whereas in the case of constant contact angle there is always a rivulet that runs all the way from the top to the bottom of the cylinder, in the case of constant width this is possible only for sufficiently narrow rivulets. Wider rivulets with constant width are possible only between the top of the cylinder and a critical azimuthal angle on the lower half of the cylinder. Assuming that the contact lines de-pin at this critical angle (where the contact angle is zero) the rivulet runs from the critical angle to the bottom of the cylinder with zero contact angle, monotonically decreasing width and monotonically increasing maximum thickness. The total mass of fluid on the cylinder is found to be a monotonically increasing function of the value of the constant width

A water vision for Johnstone

The Water Vision is based on ideas from The Netherlands which promote communication with the public on key water related issues in a local authority area. A Water Vision for Johnstone was developed in Renfrewshire, Scotland where serious flooding has occurred in the past and new, predominantly non-structural approaches to surface water management were demanded. The paper outlines the development of a ‘Water Vision for Johnstone’ which became a key outcome of the Interreg III B project ‘Urban Water’.The Water Toets (Assessments) are statutory procedures in the Netherlands which come into play from the concept stage of developments onwards to full implementation. They are undertaken jointly on behalf of the spatial planning authority and the water authorities to evaluate the impact of development on the water network. In contrast, the Water Vision is a less well-defined process to identify community needs and aspirations but in many areas the vision is essential to support the Water Toets. The Water Vision is initiated by planning officers from the municipalities asking very basic questions of their communities about what they required of the water network. It was felt that adopting such a proactive approach where virtually any question about water bodies and drainage infrastructure could be asked, would not be practicable in the UK and it was decided to assemble information about water issues in the area, the agencies involved and potential ways forward, before approaching the public.Johnstone was selected as a test area as it was felt that this locality included many of the water related problems that can be found throughout Renfrewshire. Key water issues were identified and a range of possible solutions provided. Problems, solutions and organisations responsible for different aspects of the water network are described in the document, using images and plans to facilitate the public awareness. Normally the man in the street would not be expected to be as familiar with the nature of water-related problems as the general public in the Netherlands. The Water Vision is yet to go to public consultation as it is currently primarily a planning tool in which council processes are embedded. However, it is planned that workshops including all key stakeholders involved in water management will be held. Those bodies currently responsible for water management will then be encouraged to discuss the various options and opportunities available in a creative and integrated manner. By working together as a team in addressing water related issues it will be possible to develop a vision for the future that better assists the public in moving forward together

Coupling CAD and CFD codes within a virtual integration platform

The Virtual Integration Platform (VIP) is an essential component of the VIRTUE project. It provides a system for combining disparate numerical analysis methods into a simulation environment. The platform allows for defining process chains, allocating of which tools to be used, and assigning users to perform the individual tasks. The platform also manages the data that are imported into or generated within a process, so that a version history of input and output can be evaluated. Within the VIP, a re-usable template for a given process chain can be created. A process chain is composed of one or more smaller tasks. For each of these tasks, a selection of available tools can be allocated. The advanced scripting methods in the VIP use wrappers for managing the individual tools. A wrapper allows communication between the platform and the tool, and passes input and output data as necessary, in most cases without modifying the tool in any way. In this way, third-party tools may also be used without the need for access to source code or special modifications. The included case study demonstrates several advantages of using the integration platform. A parametric propeller design process couples CAD and CFD codes to adapt the propeller to given operating constraints. The VIP template helped eliminate common user errors, and captured enough expert knowledge so that the casual user could perform the given tasks with minimal guidance. Areas of improvements to in-house codes and to the overall process were identified while using the integration platform. Additionally, the process chain was designed to facilitate formal optimisation methods

Making tracks: electronic excitation roles in forming swift heavy ion tracks

Swift heavy ions cause material modification along their tracks, changes primarily due to their very dense electronic excitation. The available data for threshold stopping powers indicate two main classes of materials. Group I, with threshold stopping powers above about 10 keV nm(-1), includes some metals, crystalline semiconductors and a few insulators. Group II, with lower thresholds, comprises many insulators, amorphous materials and high T-c oxide superconductors. We show that the systematic differences in behaviour result from different coupling of the dense excited electrons, holes and excitons to atomic (ionic) motions, and the consequent lattice relaxation. The coupling strength of excitons and charge carriers with the lattice is crucial. For group II, the mechanism appears to be the self- trapped exciton model of Itoh and Stoneham ( 1998 Nucl. Instrum. Methods Phys. Res. B 146 362): the local structural changes occur roughly when the exciton concentration exceeds the number of lattice sites. In materials of group I, excitons are not self- trapped and structural change requires excitation of a substantial fraction of bonding electrons, which induces spontaneous lattice expansion within a few hundred femtoseconds, as recently observed by laser- induced time- resolved x- ray diffraction of semiconductors. Our analysis addresses a number of experimental results, such as track morphology, the efficiency of track registration and the ratios of the threshold stopping power of various materials

Porous squeeze-film flow

The squeeze-film flow of a thin layer of Newtonian fluid filling the gap between a flat impermeable surface moving under a prescribed constant load and a flat thin porous bed coating a stationary flat impermeable surface is considered. Unlike in the classical case of an impermeable bed, in which an infinite time is required for the two surfaces to touch, for a porous bed contact occurs in a finite contact time. Using a lubrication approximation an implicit expression for the fluid layer thickness and an explicit expression for the contact time are obtained and analysed. In addition, the fluid particle paths are calculated, and the penetration depths of fluid particles into the porous bed are determined. In particular, the behaviour in the asymptotic limit of small permeability, in which the contact time is large but finite, is investigated. Finally, the results are interpreted in the context of lubrication in the human knee joint, and some conclusions are drawn about the contact time of the cartilage-coated femoral condyles and tibial plateau and the penetration of nutrients into the cartilage