4,220 research outputs found
Vacuum probe sampler removes micron-sized particles from surfaces
Vacuum probe sampler removes micron-sized particles from sensitive surfaces, without damage to the surface. The probe has a critical orifice to ensure an optimum airflow rate that disturbs the boundary layer of air and raises bacteria from the surface into the probe with the moving air stream
A collaborative platform for integrating and optimising Computational Fluid Dynamics analysis requests
A Virtual Integration Platform (VIP) is described which provides support for the integration of Computer-Aided Design (CAD) and Computational Fluid Dynamics (CFD) analysis tools into an environment that supports the use of these tools in a distributed collaborative manner. The VIP has evolved through previous EU research conducted within the VRShips-ROPAX 2000 (VRShips) project and the current version discussed here was developed predominantly within the VIRTUE project but also within the SAFEDOR project. The VIP is described with respect to the support it provides to designers and analysts in coordinating and optimising CFD analysis requests. Two case studies are provided that illustrate the application of the VIP within HSVA: the use of a panel code for the evaluation of geometry variations in order to improve propeller efficiency; and, the use of a dedicated maritime RANS code (FreSCo) to improve the wake distribution for the VIRTUE tanker. A discussion is included detailing the background, application and results from the use of the VIP within these two case studies as well as how the platform was of benefit during the development and a consideration of how it can benefit HSVA in the future
Real-time co-ordinated resource management in a computational enviroment
Design co-ordination is an emerging engineering design management philosophy with its emphasis on timeliness and appropriateness. Furthermore, a key element of design coordination has been identified as resource management, the aim of which is to facilitate the optimised use of resources throughout a dynamic and changeable process. An approach to operational design co-ordination has been developed, which incorporates the appropriate techniques to ensure that the aim of co-ordinated resource management can be fulfilled. This approach has been realised within an agent-based software system, called the Design Coordination System (DCS), such that a computational design analysis can be managed in a coherent and co-ordinated manner. The DCS is applied to a computational analysis for turbine blade design provided by industry. The application of the DCS involves resources, i.e. workstations within a computer network, being utilised to perform the computational analysis involving the use of a suite of software tools to calculate stress and vibration characteristics of turbine blades. Furthermore, the application of the system shows that the utilisation of resources can be optimised throughout the computational design analysis despite the variable nature of the computer network
A methodology for design coordination in a distributed computing environment
At the conceptual stage of the design process it is increasingly common that analysis tools are involved in the evaluation of a large number of alternative designs. Designers use such analysis tools to assist with large scale concept evaluations and the prediction of good initial designs. Consequently there exists a need to coordinate these analysis tools to enable the early stage of design to be performed in a timely and efficient manner. This paper describes a generic methodology that allows the management and coordination of design analysis tools. A Computer Aided Design tool, namely the Design Coordination System (DCS), has been developed to assist the designer in performing computational analysis in a distributed computing environment. Within the DCS, a collection of design agents act as members of a multi-functional team operating in a cooperative and coordinated manner in order to satisfy the objective of efficiently performing the design analysis
A generic coordination approach applied to a manufacturing environment
This paper describes a generic coordination approach applied to the field of manufacturing engineering. The objective of the coordination mechanism with respect to this application is twofold. Firstly, it is shown that utilising the developed system can result in the efficient organisation of processes leading to a near optimum time taken to manufacture a number of artefacts. Secondly, successful operation of the system in this environment will demonstrate that the approach is generic in nature. The results already achieved using this system within a computational analysis environment supports this hypothesis
Development of an Increased Sampling Rate Monitoring System
Sampling rate system for monitoring clean room
Microbiological studies relating to clean environments. Part I - Evaluation of the efficiency of a class 100 laminar-flow clean room for viable contamination cleanup
Laminar flow clean room efficiency for viable contamination cleanu
A methodology for prospective operational design co-ordination
Engineering companies are continually faced with the challenge of how best to utilise their design team given some design project. Decisions regarding how to distribute the project workload amongst the members of the design team are the responsibility of a project manager who, in order to do this, often relies upon previous experience and/or the support of some planning tool. Furthermore, a project manager rarely has the opportunity to assess the capability of the design team against the current work load in order to determine what, if any, alterations couldbe made to the team to facilitate appropriate reductions in project time and cost.This paper proposes a mathematical-based methodology aimed at identifying shortfalls in design teams, which if remedied would result in a more efficient project in terms of time and cost. The methodology provides a means of identifying those skills within the design team,with respect to the outstanding work load, in which improvements would have the greatest influence on reducing time and cost. In addition, the methodology employs a genetic algorithm for the purpose of scheduling tasks to be undertaken by potential design teams. The methodology is applied to two practical case studies provided by engineering industry.The first case study involves the assessment of a multi-disciplined design team consisting of single-skilled engineers. In contrast, the second case study entails the assessment of multiskilled engineers within a multi-disciplined design team. As a result of applying the methodology to the case studies, potential improvement to the design teams are identified and, subsequently, evaluated by observing their effects
Microbiological studies relating to clean environments. Part II - Deposition of nutrients to surfaces by Rodac plates
Nutrient deposition to surfaces by Rodac plates observed to evaluate microbial growth in clean environmen
Clonal mixing in the soldier-producing aphid <i>Pemphigus spyrothecae</i> (Hemiptera: Aphididae)
Illuminating the genetic relationships within soldier-producing aphid colonies is an essential element of any attempt to explain the evolution of the altruistic soldier caste. Pemphigus spyrothecae is a soldier-producing aphid that induces galls on the leaf petioles of its host (trees of the genus Populus). At least a quarter of the aphids within the clonally produced gall population are morphologically and behaviourally distinct first-instar soldiers that defend the gall population from predation. Using field trapping and microsatellites, we investigated the degree of clonal mixing within natural gall populations. Field trapping in the UK showed that all the migrants of P. spyrothecae and of two other Pemphigus species were wingless first-instar soldiers. The average degree of mixing estimated from trapping P. spyrothecae migrants was 0.68% (range = 0â15%). Microsatellite genotyping of 277 aphids from 13 galls collected in Italy revealed an average mixing level of 10.4% (range = 0â59%). Six galls contained more than one clone (range = 2â5 clones). Non-kin aphids were not restricted to the soldier caste but were evenly distributed across instars. An additional gall, from which 527 occupants were genotyped, contained 12 non-kin aphids distributed among nine clones, showing that clonal diversity can be high even when mixing is very low. These observations suggest that although soldiers migrate regularly and can moult and reproduce within foreign galls, clonal mixing in this species is generally low and is unlikely to provide a barrier to the evolution of investment by the aphid clones in an altruistic soldier caste
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