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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Friction Taper Plug Welding as a Repair Method for Fatigue Damage Around Fastener Holes in Aerospace Structures

Sumsion, David Carl 08 December 2022 (has links) (PDF)
This work details an adaptation of the friction taper plug welding (FTPW) process to repair fatigue damage in 6.35mm AA 7050 t-7451 plate. Aircraft components experience fatigue damage around fastener holes. This damage can be mitigated by enlarging fastener holes. There is no effective repair procedure once holes reach a maximum allowable size. Damaged components must be replaced. A suitable repair process would lead to substantial savings in both time and money. A simulated repair process was developed by machining holes in 6.35mm AA 7050 t-7451 plate. These hoes were then plugged using the FTPW process. Microhardness testing and metallographic analysis were used to map the effects of thermomechanical processing in a repair. Simulated repairs were machined into a tensile sample. A 6.35mm hole was bored axially through the repair center to simulate a new fastener hole. Static tensile testing was used to measure ultimate tensile strength and yield strength in the repair. Samples were also subjected to fatigue testing at stresses ranging from 170MPa to 340MPa at a stress ration of R=0.1. The same tensile and fatigue testing was done with unaltered material. A 7.94mm hole was bored through the center of this material to simulate an enlarged fastener hole. This provides baseline level of properties. Ultimate tensile strength of the base material is reduced by 15% and yield strength by 29%. Fatigue properties at a stress of 303 MPa are reduced by 22%. Fracture surfaces of poor performing samples reveal defects on the weld interface.
32

Spezifikation und Implementierung eines Plug-ins für JOSM zur semiautomatisierten Kartografierung von Innenraumdaten für OpenStreetMap

Gruschka, Erik 15 January 2016 (has links)
Der Kartendienst OpenStreetMap ist einer der beliebtesten Anbieter für OpenData-Karten. Diese Karten konzentrieren sich jedoch derzeitig auf Außenraumumgebungen, da sich bereits existierende Ansätze zur Innenraumkartografierung nicht durchsetzen konnten. Als einer der Hauptgründe wird die mangelnde Unterstützung der verbreiteten Karteneditoren angesehen. Die vorliegende Bachelorarbeit befasst sich daher mit der Implementierung eines Plug-Ins für die Erstellung von Innenraumkarten im Editor „JOSM“, und dem Vergleich des Arbeitsaufwandes zur Innenraumkartenerstellung mit und ohne diesem Hilfsmittel.
33

A composite manufacturing process for producing class A finished components / Zelldra Lombard

Lombard, Zelldra January 2014 (has links)
The purpose of this study was to develop a composite manufacturing process that would be able to deliver Class A surface finished products in the context of mould manufacturing methods. The problem required solving was to overcome the time needed to prepare Class A surfaces, by developing a composite manufacturing process that will deliver Class A surface finished products straight from the mould. The process was aimed at the entire development process, from mould and plug design up to the finished product. A literature study and a factory mould survey were conducted with a view to obtain the necessary insights into surface finishing and composite manufacturing. These surveys were followed by seven constructional tests which determined the most appropriate solutions for the proposed manufacturing processes. Test 1 was used to determine a quality finish standard for composites from the sanding grits used to finished composite surfaces versus surface roughness values used in other industries. The standard determined that a P800 finish has a roughness between 0.200 and 0.150 um and constitutes a Class A3 finish. P1000 to P1200 have a roughness between 0.150 um to 0.100 um and constitutes a Class A2 finish. Finally a P2000 and higher have a roughness of 0.100 um and lower and constitutes Class A1 surface finish. After the standard was set, the tests for finishing of the moulds, plugs and parts commenced. Test 2 was conducted on the CNC manufacturing of plugs out of Nuceron651 tooling board. Tool path parameters were varied in a matrix. The samples with the best surface finish value were cut with a step-over of 0.5 and feed of 800 mm/min. These parameters were found to be the most influential. Test 2 and 4 revealed that the plug surface finishing should commence with conventional 2K paint finishing, with a possibility of acrylic split surface. This process produced projected mould surfaces between 0.150 um and 0.200 um, which can be categorised as Class A-3. Test 5 and 6 determined methods for improving the mould surface quality and durability. It was established that the tooling gelcoat should be applied whilst being heated and backed with at least two layers of glass veil and a steady increase of GSM of structural glass fibres to prevent print-through. Test 3 determined that the mould corners could be strengthened with rovings pressed into the corner. It was also established that the moulds surfaces will require finishing after demoulding. The final moulds were manufactured from a fibreglass composite structure with tooling gelcoat surface. A number of guidelines and a set process were developed in order to produce moulds with a surface finish of average 0.9 um, equivalent to Class A1. Release agents were tested in Test 7, and the Loctite Frekote 770-NC release system was deemed appropriate for use with In Mould Coating (IMC) of 2K Paint. These elements were all synthesised into plug, mould and part manufacturing processes. The proposed processes were validated by the manufacturing of a JS instrument panel, which delivered a Class A2, 0.175 um, finish with IMC of 2K paint. With only a minor sanding of P3000 grit and polishing, the part was made into a Class A1 surface, measured at 0.63 um. The study proved that it is possible to produce Class A finished part with IMC. This method can provide a solution aimed at the elimination of P600 and lower finishing of composite parts manufactured with IMC. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014
34

A composite manufacturing process for producing class A finished components / Zelldra Lombard

Lombard, Zelldra January 2014 (has links)
The purpose of this study was to develop a composite manufacturing process that would be able to deliver Class A surface finished products in the context of mould manufacturing methods. The problem required solving was to overcome the time needed to prepare Class A surfaces, by developing a composite manufacturing process that will deliver Class A surface finished products straight from the mould. The process was aimed at the entire development process, from mould and plug design up to the finished product. A literature study and a factory mould survey were conducted with a view to obtain the necessary insights into surface finishing and composite manufacturing. These surveys were followed by seven constructional tests which determined the most appropriate solutions for the proposed manufacturing processes. Test 1 was used to determine a quality finish standard for composites from the sanding grits used to finished composite surfaces versus surface roughness values used in other industries. The standard determined that a P800 finish has a roughness between 0.200 and 0.150 um and constitutes a Class A3 finish. P1000 to P1200 have a roughness between 0.150 um to 0.100 um and constitutes a Class A2 finish. Finally a P2000 and higher have a roughness of 0.100 um and lower and constitutes Class A1 surface finish. After the standard was set, the tests for finishing of the moulds, plugs and parts commenced. Test 2 was conducted on the CNC manufacturing of plugs out of Nuceron651 tooling board. Tool path parameters were varied in a matrix. The samples with the best surface finish value were cut with a step-over of 0.5 and feed of 800 mm/min. These parameters were found to be the most influential. Test 2 and 4 revealed that the plug surface finishing should commence with conventional 2K paint finishing, with a possibility of acrylic split surface. This process produced projected mould surfaces between 0.150 um and 0.200 um, which can be categorised as Class A-3. Test 5 and 6 determined methods for improving the mould surface quality and durability. It was established that the tooling gelcoat should be applied whilst being heated and backed with at least two layers of glass veil and a steady increase of GSM of structural glass fibres to prevent print-through. Test 3 determined that the mould corners could be strengthened with rovings pressed into the corner. It was also established that the moulds surfaces will require finishing after demoulding. The final moulds were manufactured from a fibreglass composite structure with tooling gelcoat surface. A number of guidelines and a set process were developed in order to produce moulds with a surface finish of average 0.9 um, equivalent to Class A1. Release agents were tested in Test 7, and the Loctite Frekote 770-NC release system was deemed appropriate for use with In Mould Coating (IMC) of 2K Paint. These elements were all synthesised into plug, mould and part manufacturing processes. The proposed processes were validated by the manufacturing of a JS instrument panel, which delivered a Class A2, 0.175 um, finish with IMC of 2K paint. With only a minor sanding of P3000 grit and polishing, the part was made into a Class A1 surface, measured at 0.63 um. The study proved that it is possible to produce Class A finished part with IMC. This method can provide a solution aimed at the elimination of P600 and lower finishing of composite parts manufactured with IMC. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014
35

Cross-Platform, Parallel Development in Xamarin : Design and Implementation of the Platform for Building Extensible, Cross-platform GUI Applications Based on Plug-in Framework in Xamarin

Waclawek, Mariusz January 2016 (has links)
This thesis describes research of plug-in frameworks, their application and benefits and also a way to develop cross-platform GUI applications in Xamarin with Xamarin.Forms. It describes also the limitations that mobile systems set on plug-in frameworks. The result of the thesis is a basic and extensible platform for building GUI applications based on the MVVM design pattern with modularity and extensibility of MEF 2.0.
36

Computer Aided Design Tool for Electric, Hybrid Electric and Plug-in Hybrid Electric Vehicles

Eskandari Halvaii, Ali 2011 May 1900 (has links)
This research is focused on designing a new generation of CAD tools that could help a ”hybrid vehicle” designer with the design process to come up with better vehicle configurations. The conventional design process for any type of hybrid-electric vehicle would start from the vehicle performance criteria and continue by applying them to the physical models of different components of the vehicle. The final result would be strict and precise characteristics of all components in the vehicle; this scenario gives only one option for the desired vehicle. A new perspective is introduced in developing a new methodology in the art of design. This new method enables the designer to see a wider picture of what he is designing and have access to all his options and capabilities. The method is designed to help the designer ask the right questions about his design options, intelligently guide him through the design process by squeezing the space of solutions and take him to the final designed product. The new methodology is implemented in this research with the following capabilities: 1. The proposed tool allows the designer to choose any arbitrary set of variable to be known and leave the rest as the ones to be solved for; either they are vehicle component characteristic variables or performance measures. This provides a great amount of flexibility and success in designing a vehicle from any available information about it. 2. Instead of starting from single values, the new tool can work with a range of possible values for the known variables and suggest range of feasible values for the unknown variables. This provides the capability of refining the design even further and performing sensitivity analysis. 3. The proposed tool is a package that offers both design and simulation capabilities. It includes analytical performance simulation as well as simulation with arbitrary drive cycles and engine controllers. 4. Capability of 1D, 2D and 3D representation of any arbitrary set of design variables in the solution space. The idea is implemented in a pilot version software package for vehicle design.
37

Quick Orientation Viewer

Xia, Yiming January 2008 (has links)
<p>This is a plug-in project using GEF and JDT in Eclipse. The purpose for this thesis is to solve the orientation for a existing project. We can get a overview of a project such as display the class diagram of the project with the help of Orientation Viewer.</p>
38

In support of routing solutions in plug and play optical node network /

Das, Shovan, January 2007 (has links)
Thesis (M.S.)--University of Texas at Dallas, 2007. / Includes vita. Includes bibliographical references (leaves 163-166)
39

Konceptstudie på plug-and-play system / Concept study on a Plug - and - Play System

Wirén, Carina, Stanikowski, Adrian January 2018 (has links)
The report deals with a bachelor’s degree project in Product Development and Design at Jönköping University 2018. The thesis was carried out on behalf of Orkla House Care AB as the concluding part of the Mechanical Engineering program. The work was carried out by Adrian Stanikowski and Carina Wirén. The work consisted of developing an extensional concept on a plug-and-play system. Orkla House Care AB bought Anza, a manufacturer of various painting tools, in 2012. Selected products have an extensibility that gives them a more ergonomic approach to painting ceilings, walls, and floors. The existing extension system has an outgoing patent and therefore Orkla House Care has designed this project focusing on product development and construction. To get a clearer picture of what users are looking for at the product, a preliminary study was carried out. After the completion of this preliminary study, a product specification could be created. At the idea generation phase, all ideas were recorded where the product specification was omitted to avoid limiting creative thinking. The specification was then the foundation of the final concepts chosen by screening. The work focused on creating a user-friendly extension system that clearly shows the function. The focus area has primarily included the elimination of the end plug of the extensible tool, as well as avoiding the use of buttons for attachment and detachment. This focus is to avoid as many misunderstandings for the user as possible. The result of the work was a new plug-and-play system with a new design solution. / Rapporten behandlar ett examensarbete inom Produktutveckling och Design vid Tekniska Högskolan på Jönköpings University 2018. Examensarbetet utfördes på uppdrag av Orkla House Care AB som avslutande del av utbildningen Maskinteknik. Arbetet har utförts av Adrian Stanikowski och Carina Wirén. Arbetet bestod av att ta fram ett koncept på ett plug-and-play system. Orkla House Care AB köpte 2012 upp Anza som tillverkar olika måleriverktyg. Utvalda produkter erbjuder en förlängningsbarhet. Detta innebär ett mer ergonomiskt arbetssätt för att måla tak, väggar, och golv. Det befintliga förlängningssystemet har ett utgående patent och därför har Orkla House Care utformat ett examensarbete med fokus på produktutveckling och konstruktion. För att få en tydligare bild på vad användarna söker hos produkten utfördes en förstudie. Efter genomförd förstudie kunde en produktspecifikation skapas. Vid idégenereringen antecknades alla idéer ner där produktspecifikationen utelämnades för att inte begränsa det kreativa tänkandet. Specifikation låg sedan grund till de slutliga koncept som sedan valdes genom sållning. Arbetet inriktades mot att skapa ett användarvänligt förlängningssystem där funktionen tydligt framgår. Fokusområdet har främst inkluderat elimineringen av ändpluggen på det förlängningsbara verktyget samt att undvika knappsats på klickkonan. Detta för att minska missförstånd för användaren. Resultatet av arbetet var ett nytt plug-and-play system med ny designlösning.
40

GREEN ROOF PLUG GERMINATION AND GROWTH WITH DIFFERENT BASE MEDIA AND TREATMENTS

Caulkins, Afton Michelle 01 May 2017 (has links)
The germination rates of four plant species (Allium schoenoprasum L., Dianthus gratianopolitanus ‘Grandiflorus’ Vill., Sedum kamtschaticum Fisch. & C.A. Mey. Spp. ellacombianum (Praeger) R.T. Clausen, and Talinum calycinum Engelm.) were compared with six fertility treatments (control, fertilizer - once a week, double fertilizer - twice a week, mycorrhizae, vermicompost, and green roof mix) that also evaluated a peat based greenhouse medium verses a lightweight aggregate medium integrated. The greenhouse medium had higher germination rates than the lightweight aggregate medium. The control, fertilizer, and double fertilizer, which were not applied until a month into the study, provided similar germination results. The seedlings obtained from the germination study were grown into 3.81cm x 7.62cm plugs, with plant height, leaf count/width, and dry weight taken three months later. The greenhouse medium treatments control, fertilizer, and double fertilizer had the most leaves, and provided the tallest and widest leaves as well as the greatest biomass. The lightweight aggregate medium control displayed the lowest growth in this study. The fertility treatment that showed the most potential was the green roof mix. This mix significantly improved plant growth in the lightweight aggregate medium, which indicates the potential to improve greenhouse medium based plug establishment on extensive green roofs with aggregates.

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