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Reduction of Machine Tool Times Through a Software/Hardware Integrated Solution
Toolmaking is an industry that creates metal moulds, generally of durable tool steels, for
producing vacuum-formed and injection moulded plastic parts, which are used in thousands
of everyday items such as mobile phones. At present toolmaking is labour intensive with each
machining operation requiring manual supervision. The FASTOOL project was a European
Union funded collaboration that was aimed at reducing the manpower content of mould
toolmaking, and extending the working day. This paper focuses on one element which utilised
specially created scheduling and control software that operated an automated overhead gantry
system and could remotely start the workshop machines. The software was completely object
oriented which allows future proofing by creating new objects for new machines. The results
demonstrate that this manufacturing process can be automated, leading to better working
conditions for employees and an increase in efficiency and profitability.Mechanical Engineerin
Long term orbital inclination and eccentricity oscillations of the planets in our solar system
The orbits of the planets in our solar system are not in the same plane, therefore natural torques stemming from Newton’s gravitational forces exist to pull them all back to the same plane. This causes the inclinations of the planet orbits to oscillate with potentially long periods and very small damping, because the friction in space is very small. Orbital inclination changes are known for some planets in terms of current rates of change, but the oscillation periods are not well published. They can however be predicted with proper dynamic simulations of the solar system.
A three-dimensional dynamic simulation was developed for our solar system capable of handling 12 objects, where all objects affect all other objects. Each object was considered to be a point mass which proved to be an adequate approximation for this study. Initial orbital radii, eccentricities and speeds were set according to known values. The validity of the simulation was demonstrated in terms of short term characteristics such as sidereal periods of planets as well as long term characteristics such as the orbital inclination and eccentricity oscillation periods of Jupiter and Saturn. A significantly more accurate result, than given on approximate analytical grounds in a well-known solar system dynamics textbook, was found for the latter period.
Empirical formulas were developed from the simulation results for both these periods for three-object solar type systems. They are very accurate for the Sun, Jupiter and Saturn as well as for some other comparable systems
Variable-Number-of-Tandem-Repeats Analysis of Genetic Diversity in Pasteuria ramosa
Variable-number-of-tandem-repeats (VNTR) markers are increasingly being used in population genetic studies of bacteria. They were recently developed for Pasteuria ramosa, an endobacterium that infects Daphnia species. In the present study, we genotyped P. ramosa in 18 infected hosts from the United Kingdom, Belgium, and two lakes in the United States using seven VNTR markers. Two Daphnia species were collected: D. magna and D. dentifera. Six loci showed length polymorphism, with as many as five alleles identified for a single locus. Similarity coefficient calculations showed that the extent of genetic variation between pairs of isolates within populations differed according to the population, but it was always less than the genetic distances among populations. Analysis of the genetic distances performed using principal component analysis revealed strong clustering by location of origin, but not by host Daphnia species. Our study demonstrated that the VNTR markers available for P. ramosa are informative in revealing genetic differences within and among populations and may therefore become an important tool for providing detailed analysis of population genetics and epidemiolog
3D Particle Tracking Velocimetry Method: Advances and Error Analysis
A full three-dimensional particle tracking system was developed and tested. By using three separate CCDs placed at the vertices of an equilateral triangle, the threedimensional location of particles can be determined. Particle locations measured at two different times can then be used to create a three-component, three-dimensional velocity field. Key developments are: the ability to accurately process overlapping particle images, offset CCDs to significantly improve effective resolution, allowance for dim particle images, and a hybrid particle tracking technique ideal for three-dimensional flows when only two sets of images exist. An in-depth theoretical error analysis was performed which gives the important sources of error and their effect on the overall system. This error analysis was verified through a series of experiments, which utilized a test target with 100 small dots per square inch. For displacements of 2.54mm the mean errors were less than 2% and the 90% confidence limits were less than 5.2 μm in the plane perpendicular to the camera axis, and 66 μm in the direction of the camera axis. The system was used for flow measurements around a delta wing at an angle of attack. These measurements show the successful implementation of the system for three-dimensional flow velocimetry
On imploding cylindrical and spherical shock waves in a perfect gas
The problem of a cylindrically or spherically imploding and reflecting shock wave in a flow initially at rest is studied without the use of the strong-shock approximation. Dimensional arguments are first used to show that this flow admits a general solution where an infinitesimally weak shock from infinity strengthens as it converges towards the origin. For a perfect-gas equation of state, this solution depends only on the dimensionality of the flow and on the ratio of specific heats. The Guderley power-law result can then be interpreted as the leading-order, strong-shock approximation, valid near the origin at the implosion centre. We improve the Guderley solution by adding two further terms in the series expansion solution for both the incoming and the reflected shock waves. A series expansion, valid where the shock is still weak and very far from the origin, is also constructed. With an appropriate change of variables and using the exact shock-jump conditions, a numerical, characteristics-based solution is obtained describing the general shock motion from almost infinity to very close to the reflection point. Comparisons are made between the series expansions, the characteristics solution, and the results obtained using an Euler solver. These show that the addition of two terms to the Guderley solution significantly extends the range of validity of the strong-shock series expansion
Systems Development of a Two-Axis Stabilised Platform to Facilitate Astronomical Observations from a Moving Base
This project aimed to design, simulate, and implement a two-axis inertially
stabilised platform (ISP) for use in astronomical applications. It aimed to
approximate the stabilisation of a Meade ETX-90 3.5" compound telescope at
low-cost using a mechanical assembly designed to geometrically and inertially
model the telescope. A set of system specifications was developed to guide
design decisions and to provide an analysis framework against which the
performance of the implemented system was compared. The electro-mechanical
structure of the ISP was designed and manufactured, the associated electrical
systems were specified and configured, an image processing script capable of
detecting and locating the centre of the Moon in a camera field-of-view was
written, a complete simulation model for the system was developed and used to
design various classical controllers for the ISP control system. These
controllers were implemented on a STM32F051 microcontroller and a user
interface was written in LabVIEW to facilitate intuitive user control of the
system and perform datalogging of the system runtime data.Comment: 2019 Southern African Universities Power Engineering
Conference/Robotics and Mechatronics/Pattern Recognition Association of South
Africa (SAUPEC/RobMech/PRASA
The 2mrad horizontal crossing angle IR layout for a TeV ILC
The current status of the 2mrad crossing angle layout for the ILC is
reviewed. The scheme developed in the UK and France is described and the
performance discussed for a TeV machine. Secondly, the scheme developed at SLAC
and BNL is then studied and modified for a TeV machine. We find that both
schemes can handle the higher energy beam with modifications, and share many
common features.Comment: The proceedings of the 2005 International Linear Collider Workshop,
March 2005. 4 pages, 5 figure
MUN Festival and Chamber Choirs, Douglas Dunsmore, conductor (April 7, 1991)
MUN Festival and Chamber Choirs, Douglas Dunsmore, conductor (April 7, 1991
The Exodus Route considering all Biblical Information, Part 2
All biblical information, geographic information mostly with Google Earth Pro and some archaeological evidence were investigated to determine the exodus routes of Israel as accurately as possible. The plural “routes” is sometime used because of the distinctive phases of the 40-year journey. Some archaeological evidence points to the Red Sea crossing in the Gulf of Aqaba and the mountain of Horeb or Sinai to be in Saudi Arabia, which are not only consistent with biblical information but is strongly suggested by the Bible. Comparing the exodus route information in different books in the Bible and with some identified Google Earth Pro locations also indicates the disobedience of Israel in the last year before entering Canaan by wanting to go their own route, but God forced them by calamities to ask for rescue and to turn around and travel along the border between Edom and Moab eventually to the east of the Jordan river. This is Part 2 of the article
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