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Topological Data Analysis of Properties of Four-Regular Rigid Vertex GraphsConine, Grant Mcneil 24 June 2014 (has links)
Homologous DNA recombination and rearrangement has been modeled with a class of four-regular rigid vertex graphs called assembly graphs which can also be represented by double occurrence words. Various invariants have been suggested for these graphs, some based on the structure of the graphs, and some biologically motivated.
In this thesis we use a novel method of data analysis based on a technique known as partial-clustering analysis and an algorithm known as Mapper to examine the relationships between these invariants. We introduce some of the basic machinery of topological data analysis, including the construction of simplicial complexes on a data set, clustering analysis, and the workings of the Mapper algorithm. We define assembly graphs and three specific invariants of these graphs: assembly number, nesting index, and genus range. We apply Mapper to the set of all assembly graphs up to 6 vertices and compare relationships between these three properties. We make several observations based upon the results of the analysis we obtained. We conclude with some suggestions for further research based upon our findings.
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Factors leading to offshore manufacture of Australian inventions : the case of the orbital combustion process engineKaren Jane Manley January 1994 (has links)
This thesis focuses on the factors which lead to off-shore manufacture of Australian inventions. It establishes this phenomenon as a problem, both in terms of its incidence in the post-war period, and in the strategic importance of innovative activity to economic growth. The thesis utilises a case study approach and concentrates on the experiences of one company, the Orbital Engine Corporation (Orbital). In 1989 Ralph Sarich, inventor of the Orbital Combustion Process (OCP) engine and founder of Orbital, signed an agreement with the Michigan state government to manufacture the engine in the United States of America (USA), in preference to several alternative sites in Australia and overseas. This occurred in the context of Orbital actively pursuing assistance from the Australian government to secure local production. The research question is: Why did Orbital decide to manufacture its engine invention ofshore? A multi-disciplinary approach to this question is adopted. Three different conceptual frameworks are employed: industrial organisation theory, market failure theory and policy network theory. The analysis is not structured around a pre-existing hypothesis; instead, the aim is to generate potential explanations for more rigorous testing by subsequent researchers.
The thesis concludes that, in terms of industrial organisation theory, the decision to manufacture OCP engines off-shore was a function of the poor quality of the Australian industrial context and the failure by those seeking assistance from the Commonwealth government to stress Orbital's status as an exemplary enterprise in Australian industry. Market failure theory indicated that offshore production of the OCP engine was made more likely by the suboptimal operation of the price mechanism, the neglect of market failure arguments by those supporting local production of the engine and 'government failure'. Policy network theory explained Orbital's decision as the result of: ineffective employment of negotiation tactics by proponents of the engine's domestic manufacture; and the chaotic nature of negotiations which allowed certain personal and ideological prejudices to dominate the issue resolution process.
It is shown that some or all of these explanations underlie a number of other examples where Australian inventions have been manufactured offshore. In commenting on policy implications, the thesis points to the economic potential of the Orbital invention and the value of interventionist industry policy. The thesis identifies a number of actions which might be taken to lower the incidence of foreign manufacture of Australian inventions. Further research is necessary to determine the relative importance of the various factors which are identified as leading to offshore production. In addition, there remains a particularly crucial need to improve the social efficiency of existing cost-benefit techniques employed by government policy-makers and commercial analysts.
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A study of hybridisation of DNA immobilised on gold: strategies for DNA biosensingMearns, Freya Justine, Chemistry, Faculty of Science, UNSW January 2006 (has links)
This thesis outlines a study of the physical changes that hybridisation imposes on single-stranded DNA (ssDNA) immobilised by one end to a substrate, and of how such physical changes can be exploited to detect specific sequences of DNA in a target solution. The system studied was composed of a mixed monolayer of 20mer ssDNA with C6 alkanethiolate modifications on their 3??? ends and short-chain hydroxyterminated alkanethiolates, on a gold substrate. It was prepared using the self-assembly properties of alkanethiols on gold. Atomic force microscopy images showed that the end-immobilised ssDNA is flexible enough to lie over the diluent hydroxy-terminated self-assembled monolayer (SAM). Hybridisation was shown to cause the DNA to become more rigid and stand up off the substrate due to an increase in persistence length. Such physical changes of the DNA upon hybridisation were significant enough to be exploited in the development of a DNA recognition interface. The recognition interface was designed with the view of keeping it both simple to make and simple to use, and was coupled with electrochemical transduction. A label-free recognition interface was developed that relied on the oxidation of the sulfur head group of the alkanethiolate SAM to detect hybridisation (firstly air oxidation and then electrochemical oxidation). It produced a positive signal upon hybridisation with complementary target DNA. Improvements in the reliability and robustness of the recognition interface were made using a labelled approach. The labelled version employed electroactive molecules as labels on the 5??? ends of the probe DNA strands. Two labels were investigated ??? anthraquinone and ferrocene. The flexibility of the ssDNA ensured that the redox labels were able to directly access the underlying gold electrode. Hybridisation was expected to remove the labels from the electrode due to an increase in the DNA???s persistence length, and thus perturb the electrochemical signal. The use of ferrocene as a label provided a ???proof-of-concept??? for the system. The labelled recognition interface provides a foundation for the future development of a simple, reliable, and selective DNA hybridisation biosensor.
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Structure and physical properties of surfactant and mixed surfactant films at the solid-liquid interface.Blom, Annabelle January 2005 (has links)
The adsorbed layer morphology of a series of surfactants under different conditions has been examined primarily using atomic force microscopy (AFM). The morphologies of single and double chained quaternary ammonium surfactants adsorbed to mica have been characterised using AFM at concentrations below the cmc. Mixing these different types of surfactants systematically allowed a detailed examination of the change in adsorbed film curvature from the least curved bilayers through to most curved globules. From this study a novel mesh structure was discovered at curvatures intermediate to bilayers and rods. A mesh was again observed in studies examining the morphology change of adsorbed nonionic surfactant films on silica with variation in temperature. Other surfactant mixtures were also examined including grafting non-adsorbing nonionic surfactants and diblock copolymers into quaternary ammonium surfactant films of different morphologies.
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Robotiserad montering av styrskåp / Automated Assembly of a Control Cabinet Using a RobotTörnqvist, Martin January 2010 (has links)
<p>Syftet med detta arbete var att undersöka möjligheterna för montering av ett styrskåp av modell Motoman NX100 NOC1. För detta användes simuleringsprogrammet DELMIA. Roboten som användes nådde inte alla montage om skåpet var stationärt. Därför prövades först ett antal olika förslag för att lösa detta problem genom att transportera skåpet. Det koncept som bedömdes som mest pålitligt användes sedan för att skapa en mer ingående simulering. Detta koncept bygger på en U-formad transportbana med växlingssektioner. Skåpet transporteras först så att montage kan ske på dess framsida. När skåpet har transporterats runt till motsatt sida om roboten, kan montage utföras på skåpets baksida. Konceptet inkluderar montering av skåpets huvudkomponenter. Utrymmeskrav för hantering och infästning av komponenter undersöktes. Montering av kablage är relativt tidskrävande att modellera i DELMIA, så detta var därför inte möjligt att genomföra inom projektets omfattning. Därför har det utelämnats från simuleringen.</p><p>Roboten som användes var Motoman SDA10, vilken består av två armar. Detta har använts för att undvika verktygsväxling och specialverktyg. Robotens ena arm sköter hantering av komponenter med ett vakuumgripdon. Den andra armen hanterar två olika skruvdragare med hjälp av ett fingergripdon. Den ena skruvdragaren har skruvmatning, medan den andra används för efterdragning. Båda skruvdragare har handtag anpassade för robotens fingergripdon.</p><p>I konceptet ingår en lösning för att montera komponenter på skåpets dörr, i det fallet att dörren redan har monterats på skåpet.</p><p>En analys gjordes för att finna vilka svårigheter som finns hos en manuell montering av styrskåpet. Förslag på anpassningar togs fram, där avsikten var att förenkla skåpets montage. Analysmetoden som användes var Product Design for Assembly av Boothroyd G. & Dewhurst P. (1991). Tidsuppskattningarna som togs fram med hjälp av denna metod visade att cykeltiden kan reduceras med 24% genom att implementera anpassningsförslagen. Tidsuppskattningarna är dock endast baserade på montage av skåpets huvudkomponenter. Montering av kablage inkluderas inte i tiderna, då det är utanför omfattningen av detta projekt. Vissa av anpassningarna avser att minska antalet skruvtyper som används vid komponenternas infästning.</p>
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Robotized assembly simulation of a couplingKlevendal, Niklas January 2010 (has links)
<p>The goal of this master´s thesis is to simulate a robotized assembly of a small model of VBG Group couplings. By the software; Process simulate has the simulation model built up and the simulation been done. The simulation model is built up of the coupling parts and resources; conveyor, fixtures, compress machine, grippers, nut and screw sorter. All parts and resources, except the compress machine, the fixture and cage for the shaft, have been designed under the whole project. A study on how assembly simulation works in the software has also been done.</p>
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Concept for a modular assembly direct drive permanent magnet generator : Development of model and winding schemeSkoog, Henric January 2010 (has links)
<p>In this thesis, a concept for a modular assembly direct drive permanent magnetgenerator is presented. The maximum forces that act on the different parts of thegenerator during normal operation have been calculated and used in solid mechanicsimulations in SolidWorks. The result is a rough first draft of a generator designwhere the stator has been divided into five modules and the rotor into six modules.This division is done in order to avoid symmetries in the generator that could lead toproblems with self-oscillation.The modulization of the stator brings about certain difficulties, both for the magneticcircuit and for the winding scheme. Different solutions for optimization of themagnetic circuit are analyzed from both a physical and a construction technicalperspective. A winding scheme is produced and the winding process tested in awinding dummy produced according to the conceptual generator design.</p>
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Nanopatterning by Swift Heavy IonsSkupinski, Marek January 2006 (has links)
<p>Today, the dominating way of patterning nanosystems is by irradiation-based lithography (e-beam, DUV, EUV, and ions). Compared to the other irradiations, ion tracks created by swift heavy ions in matter give the highest contrast, and its inelastic scattering facilitate minute widening and high aspect ratios (up to several thousands). Combining this with high resolution masks it may have potential as lithography technology for nanotechnology. Even if this ‘ion track lithography’ would not give a higher resolution than the others, it still can pattern otherwise irradiation insensitive materials, and enabling direct lithographic patterning of relevant material properties without further processing. In this thesis ion tracks in thin films of polyimide, amorphous SiO<sub>2</sub> and crystalline TiO<sub>2</sub> were made. Nanopores were used as templates for electrodeposition of nanowires.</p><p>In lithography patterns are defined by masks. To write a nanopattern onto masks e-beam lithography is used. It is time-consuming since the pattern is written serially, point by point. An alternative approach is to use self-assembled patterns. In these first demonstrations of ion track lithography for micro and nanopatterning, self-assembly masks of silica microspheres and porous alumina membranes (PAM) have been used. </p><p>For pattern transfer, different heavy ions were used with energies of several MeV at different fluences. The patterns were transferred to SiO<sub>2</sub> and TiO<sub>2</sub>. From an ordered PAM with pores of 70 nm in diameter and 100 nm inter-pore distances, the transferred, ordered patterns had 355 nm deep pores of 77 nm diameter for SiO<sub>2 </sub>and 70 nm in diameter and 1,100 nm deep for TiO<sub>2</sub>. The TiO<sub>2</sub> substrate was also irradiated through ordered silica microspheres, yielding different patterns depending on the configuration of the silica ball layers. </p><p>Finally, swift heavy ion irradiation with high fluence (above 10<sup>15</sup>/cm<sup>2</sup>) was assisting carbon nanopillars deposition in a PAM used as template. </p>
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Integrated methodology for board assignment and component allocation in printed circuit board assemblyNeammanee, Patcharaporn 20 September 2001 (has links)
The purpose of this research is to develop an approach to minimize
makespan for assigning boards to production lines. Because of sequence-dependent
setup issue, board assignment and component allocation have to be performed
concurrently. An integrated methodology is proposed to obtain a solution of the
two problems. The methodology consists of seven phases: PCB grouping, family
decomposition, subfamily sequencing, Keep Tool Needed Soonest (KTNS),
component setup determination, component allocation, and board assignment.
PCB grouping based on component similarity between boards is used to
reduce the problem size. Family decomposition is used when total number of feeder
slots required by a family exceeds feeder capacity. Subfamily sequencing and Keep
Tool Needed Soonest are applied to minimize the number of component setups.
Classification of setup components into standard, semi-standard, and custom setup
components is performed to reduce the complexity of the component allocation
problem. A component allocation algorithm is developed to balance workload
across machines. Assigning board families to production lines is performed using a
modification of Longest Processing Time (LPT) rule. Assigning entire PCB
families to production lines to minimize makespan is difficult to accomplish since
the amount of production time for each family is very large compared to that of
individual PCB lot. Splitting some subfamilies is allowed as long as this does not
increase makespan. The PCB grouping, family decomposition, subfamily
sequencing, Keep Tool Needed Soonest (KTNS), and component setup
determination procedures are derived from published research results. The
component allocation and board assignment are developed in this research, as well
as an overall methodology to integrate the entire problem.
Data provided by published literature are employed to evaluate performance
of the component allocation algorithm and the integrated methodology. To examine
the applicability of the methodology, an industrial data is used with the total
imbalance due to setup time and placement time of individual PCB and global
makespan as the performance measures. Experimentation is conducted with
simulated data based on an industry data to investigate impact of threshold value,
feeder capacity, and characteristics of data sets on system performance. / Graduation date: 2002
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Monitoring and diagnosis of a multi-stage manufacturing process using Bayesian networksWolbrecht, Eric T. 25 June 1998 (has links)
This thesis describes the application of Bayesian networks for monitoring and
diagnosis of a multi-stage manufacturing process, specifically a high speed production
part at Hewlett Packard. Bayesian network "part models" were designed to represent
individual parts in-process. These were combined to form a "process model", which is a
Bayesian network model of the entire manufacturing process. An efficient procedure is
designed for managing the "process network". Simulated data is used to test the validity
of diagnosis made from this method. In addition, a critical analysis of this method is
given, including computation speed concerns, accuracy of results, and ease of
implementation. Finally, a discussion on future research in the area is given. / Graduation date: 1999
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