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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.
151

Utvärdering av mätplan, pinjong : För kortade bearbetningstider och ökade toleranser i monteringen

Elvén, Per, Gustafsson, Henrik January 2007 (has links)
Getrag All Wheel Drive i Köping tillverkar i huvudsak transmissioner till fyrhjulsdrivna bilar. De har sett en besparingspotential om det är möjligt att sluta tillverka ett mätplan på pinjonghuvudets ovansida, detta används för att mäta in pinjongläget vid slutmonteringen av växlarna. I perioder har det uppstått kassationer på grund av slipbränningar på mätplanet men en stor del av besparingen ligger i kortade bearbetningstider. En önskan har även varit att det skall gå att få en ökad toleransvidd i monteringen för att minska antalet justeringar av monterade växlar. För att utreda om det skulle vara möjligt att ta bort mätplanet har ett antal koncept arbetats fram för att utvärderas gentemot de kriterier som måste uppfyllas. Konceptet med störst potential valdes ut med hjälp av olika jämförelsemetoder. Studien visar att det finns en möjlighet att bestämma pinjongläget genom att mäta i dubbhålet. De ändringar som måste göras är: - Ny mätstation vid inmätning av pinjonglägesshims där tjockleken på pinjonghuvudet mäts. - Ny meshingstation där pinjongen orienteras med hjälp av ett lagrat kontrollvärde istället för att lokalisera med hjälp av mätplanet. - Ny kontrollstation för inmätning av pinjonghöjd där det måste gå att lokalisera växelhuset för att kompensera för lutningen på grund av att det inte går att mäta rakt under röraxelns centrumlinje. Möjligheten att helt utesluta mätmetoden bör undersökas
152

The Analysis of The Disputes in Construction Contact

Lu, Shih-Chin 12 August 2005 (has links)
The properties of Construction Engineering include: (1) high building cost, (2) unpredictability of construction risk because of the fact that the period of executing the contract is long and the external environment is easy to change, (3) the phenomena that disputes and conflicts happen easily since a construction project normally requires a large number of constructing units, each of which owns their complicated construction technology and expertise. As the process of the construction project involves various risks, the awareness of these risks and the method of diversifying the risks become important. This dissertation focuses on study of the legal aspects of the construction contact; It first tries to analyze the properties of the construction contract, its related properties which cause higher risks than contract with consideration, and different types of disputes and conflicts in common dispute decision and arbitration judgment in construction projects. Then it studies the commitment resulting from the disputes, and the comments on disputes of same kind in the real cases. Further it makes a basic proposition to the comments. Finally it examines the feasibility of the proposition through interviewing with some experts (adopting the method of Delphi). Meanwhile it modifies the proposition and adds more comments onto it proposition, in the hope that both of the owner and the contractor can prevent the disputes at the time of making contract.¡@ In most of the real case, the owners normally transfer the risks they should have taken to the contractors. This way of distributing risks may not either bring efficiency or benefits to the contract; instead it brings more losses to both sides. There are no many clauses in the section Hire of Work in Civil Code regarding distribution of risks. Those clauses leave incomplete resolution of various risks likely to happen in the contract. Therefore it is necessary to emphasize the principles of risk distribution in the construction contract¡Gmainly the just and reasonable principle, principle of change of circumstances, and principle of good faith, etc. The construction conventions can be referred too, such as convention of project fact, and the commom law which ie formed of the opiom by the court¡Barbitration judgment¡Bmediation¡C
153

Förbättring av väggfäste för flatscreens

Pettersson, Jonas, Rinman, Alfred January 2006 (has links)
<p>The project was carried out in cooperation with the department of product development IOS at IKEA. The work included improvements of a new existing product that Ikea soon will release on the market, Observatör, a wall bracket for flat screens. The product is supposed to fulfil the needs within this market for IKEA. However, since Ikea was not satisfied with it, our work was to carry out the improvements that were specified in the beginning of the project. Another task in the project was to develop a side-product that is supposed to be used together with Obeservatör for storage of DVD/decoders.</p><p>The project included labour as problem definition to final technical drawings and a prototype. In the project start information was gathered to understand the current market and its competition. The next step was to start solving the problem in a creative way through brainstorming and concept drawings. When the final concepts were chosen they were developed into final solutions with technical drawings.</p><p>The final result meets the main requirements that were stated in the beginning of the project. The wall bracket is now in two main parts that will make the assembly on the wall easier, the joints between the parts and the shafts works smother at the same time as the demands for tilt, rotation etc. works successfully. The final result is two user friendly products, Observatör and storage for DVD/decoders that have the same interface so the costumer easy can see that they are supposed to be used together.</p>
154

Konstruktion rörklammer

Dalslätt, Göran January 2007 (has links)
<p>This report describes the development process of a pipe clamp used on exhaust system for cars. It is made based on the manufacturers desire to improve and make the clamp easier to manufacture and to reduce its price to their customers. This should be done either by manufacturing the clamp in one piece without an expensive and work intensive welding process, or by generating ideas of how to develop a brand new type of clamp. Investigating the market for similar products was done to eliminate intrusion of other manufacturers’ patents but also to generate ideas. Making drawings of the many ideas gave a concept of three concepts called existing clamp in one piece, existing clamp by several pieces and innovation solutions. Some of these ideas were investigated further and were 3D modelled in pro-engineer and necessary drawing files were made to be used in the manufacturing of several prototypes. One of the solutions resulted in a prototype that was manufactured by handmade tools and the results of the tests was very positive. The clamp was strong enough to join the pipes together very well without breaking. It was manufactured in one piece and formed in five steps without any welding operations instead of the seven steps, including welding, that is used on the clamp today. The prototype requires 25 % more material and most of it is scrap from the cutting operation.</p>
155

Vibrationsisolering av gruvmaskinshytt

Berg, Kristoffer, Lindholm, Jonas January 2007 (has links)
<p>Detta examensarbete, på uppdrag av Atlas Copco Rock Drills AB, syftar till att kartlägga de problem gällande vibrationer som finns och uppstår vid användandet av produkten Scaletec MC och komma med förslag till lösningar på ett nytt system som bättre hanterar vibrationer än det befintliga. Lösningarna är avgränsade till hytten och hyttens koppling mot ramen. Kartläggningen av Scaletec MC visade att den största problemskaparen är den långa bommen med den tunga hydraulhammaren framtill. Den skapar rörelse i hytten både vid skrotning och vid transport. Vid transport är även den odämpade stolen, de ojämna vägarna och det faktum att axlarna är stela ett stort problem som genererar helkroppsvibrationer hos operatören. Konceptfasen fokuserade på att hitta en robust och kompakt konstruktion som med rätt val av frihetsgrader skulle kunna lösa de existerande problemen med vibrationer. Arbetet resulterade i två lösningar som på ett kontrollerat sätt hanterar de vibrationer som uppstår vid skrotning och transport. Det ena konceptet syftar till att åtgärda de brister dagens system besitter medan det andra även är anpassat för att hantera större vibrationsnivåer.</p> / <p>The aim of this thesis, commissioned by Atlas Copco Rock Drills AB, is to investigate the vibration problems concerning the Scaletec MC and give proposals on new concept solutions that improve the handling of the vibration problems. The solutions are limited to the cabin and the cabins connection to the frame. The conclusion tells us that the most important issue is the long reaching boom with the hydraulic hammer attached to it. This assembly creates movements in the cabin during scaling and transportation. The non-damped transportation chair, the rough roads and the stiff axles are also factors that create problems with whole body vibrations. </p><p>The concept phase focused on finding a robust and compact design that, with the correct degree of freedoms, reduces the influence of the vibrations. The result consists of two solutions, both controlling and managing the existing vibrations. The first solution focuses on the flaws that the existing system possesses and the other is designed to handle greater vibration levels.</p>
156

Statusbedömning och förbättringsförslag för startkedjemaskineri, startkedja och linspel för stränggjutningsmaskin

Lago, Mattias, Sunesson, Pavel January 2008 (has links)
<p>The main goal with the master thesis has been to do a status evaluation of the chain machinery with its start chain and wire to secure the production on a short basis due to that a reconstruction is not planned at this time. An evaluation of the condition of the start chain and the rollers in the chain depository has been done. An offer has been requested for a new start chain and the evaluation of the start chains may be a basis for the decision taking. The production has been able to go on, although it has arisen some problems which have been difficult to find the causes for. There is no gathered “picture” of the machinery status and a mapping of each machinery has been compiled of comprehensive logs. Observations and measurements have also been done to prove and elucidate the biggest problems.</p><p>After the compilation a concentration has been done of the two most frequently problems during the last years, that is to say, 2006 to 2008. The work has finally fallen into suggestions for improvements of routines and suggestions for concepts for construction changes to keep a continuous stable production until a bigger reconstruction will be made.</p><p>The two problems which have been focused on were the “limit-switches” for the wires and the heat-radiation-shields situated under the tilt bridges. The arrangement for the wire problem shown to be quite simple to implement and its cause was due to that the friction was to big in the shackle, which function is to be pressed down by the wire, and thereby didn’t trigger an alarm on the computer screens.</p><p>To prevent this, lubrication was done for respective shackle to sustain the production for a short period of time. Although there have been done some concepts to sustain the production for a longer period of time.</p><p>The problems concerning the heat-radiation-shields under the tilt bridges can be solved mainly by changed maintenance routines, which have been attached in the list which has been formed.</p>
157

Brandskydd av stålprofiler / Fireprotection of steel sections

Holmgren, Anna January 2002 (has links)
<p>Denna rapport är resultatet av en studie kring kostnader för brandskydd av stålprofiler. </p><p>Rapporten inleds med en beskrivning av problemet att hitta den ekonomiskt bästa lösningen för brandskydd av stålpelare i en konstruktion med specificerad brandklass. Därefter följer en allmän del om brandskydd och en övergripande redogörelse för gällande lagar och föreskrifter som har betydelse för brandskyddsdimensioneringen. De laster och förutsättningar som ligger till grund för valet av pelardimensioner beskrivs och valda dimensioner redovisas i tabell. Därefter följer en beskrivning av de brandskyddsmaterial som studerats: inklädnad med gips-, fibersilikat-, och stenullsskivor samt brandskyddsmålning. I resultatet ingår en sammanställning i tabellform. Till rapporten hör ett antal bilagor med materialspecifika tabeller samt resultat från gjorda datorberäkningar. </p> / <p>This report is the result of a study on costs for fire protection of steel sections. </p><p>The report starts with a description of the problem to find the most economic way to protect a steel column in a construktion with a specified fire classification. After this follows a general part about fire protection and then a comprehensive account of valid laws and regulations of importence for the dimensioning of the fire protect. Loads and other conditions that underlies the choice of column dimensions is described and chosen dimensions are shown in a table. Then follows a description of the materials for fire protection which is concidered: cladding with plaster-, fibre silicate-, and stone wool XXX and XXXpaint. The result includes a compilation table. To the report comes a number of appendix with specific material tables and results from the computer calculations.</p>
158

Jämförelse av produktionsmetoder vid byggande av gång- och cykeltunnel. / Productions of a pedestrian and cyclist tunnel. Comparison between productions methods.

Aronsson, Mattias, Karlsson, Jimmy January 2003 (has links)
<p>Vi har i denna rapport jämfört produktionsmetoder vid byggande av gång- och cykeltunnel under järnväg. de metoder vi har jämfört är lansering och platsgjutning. Projektet som vi har studerat är byggandet av en gong- och cykeltunnel under järnväg vid Mjölby station. Vid detta projekt lanseras halva tunneln in och halva platsgjuts. </p><p>Det vi har jämfört är dels de geotekniska aspekterna, där vi främst har tittat på vikten av förundersökningar, jordegenskapens inverkan, spontning och grundvattnets inverkan. Vi har också tittat på produktionstekniska aspekter, då främst storleken av arbetsområdet och arbetsmiljön. Vi har även betraktat ekonomi och produktionstid i de båda metoderna. </p><p>Vi har i denna rapport främst använt oss av muntliga källor som gett sina synpunkter på hur tunneln ska eller bör utformas. Vi har sedan sammanställt alla synpunkter och åsikter och skaffat oss en egen uppfattning om de båda metoderna och när de bör användas. </p><p>Det vi kommit fram till när vi har jämfört dessa båda metoder är att lansering har många fördelar vad gäller arbetsmiljö, tid och ekonomi. vid enklare tunnelprojekt är denna metod att föredra om förutsättningar finns. platsgjutning har dock de fördelar att den kan användas vid de flesta tunnelbyggnationer och att tågtrafiken kan flyta på utan längre störningar. </p><p>Vid stora projekt som det i Mjölby anser vi att en kombination av metoderna är den allra bästa lösningen.</p>
159

Inneluftsventileradekryprumsgrunder : en utvärdering av två tillverkare / Internal air ventilated crawl-space : an evaluation of two manufactures

Rönngren, Andreas January 2002 (has links)
<p>This Diploma work investigates internal air ventilated crawl-space in respect to construction and damp. The Diploma work assumes from a general description of crawl-space and general dump problems in ground construction. </p><p>An internal air ventilated crawl-space is a construction where you take the ventilation air from the building and bring it down to the crawl-space and lets the air circulate before it passes through a retaining aggregate on the way out from the crawl-space. In this matter you get a worm space under the building and a lot less dump problems in form of </p><p>· Ground damp </p><p>· Build damp </p><p>The ground dump reduces through draining around the building, different layer of gravel between the ground and the building and ventilation of the crawl- space. The build dump reduces through ventilation of the crawl-space as fast as possible. </p><p>To make a internal air ventilated crawl-space work as it is thought it demands that the construction is completely airtight, or else you can get air leakage that makes warm air to leak out and could air can come in. </p><p>From the literature study about internal air ventilated crawl-space and dump I have evaluated two different manufactures and have discovered that the differences according to construction problems and dump problems is marginal.</p>
160

Konstruktion rörklammer

Dalslätt, Göran January 2007 (has links)
This report describes the development process of a pipe clamp used on exhaust system for cars. It is made based on the manufacturers desire to improve and make the clamp easier to manufacture and to reduce its price to their customers. This should be done either by manufacturing the clamp in one piece without an expensive and work intensive welding process, or by generating ideas of how to develop a brand new type of clamp. Investigating the market for similar products was done to eliminate intrusion of other manufacturers’ patents but also to generate ideas. Making drawings of the many ideas gave a concept of three concepts called existing clamp in one piece, existing clamp by several pieces and innovation solutions. Some of these ideas were investigated further and were 3D modelled in pro-engineer and necessary drawing files were made to be used in the manufacturing of several prototypes. One of the solutions resulted in a prototype that was manufactured by handmade tools and the results of the tests was very positive. The clamp was strong enough to join the pipes together very well without breaking. It was manufactured in one piece and formed in five steps without any welding operations instead of the seven steps, including welding, that is used on the clamp today. The prototype requires 25 % more material and most of it is scrap from the cutting operation.

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