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1707 Uppsatser om Keywords: vacuum circuit breaker - Sida 8 av 114
Omkonstruktion av treaxlig plockrobot och dess plockverktyg
This thesis has treated a three-axis robot which task is to serve a larger test machine tomove the modules to be tested, from the storage to the test site. The robot is composed ofthree linear actuators; two standard components of ball screw type and a custom-builtactuator of trapezoidal type. The work has mainly focused on the custom-built device to seeif it could be replaced with a standard component. Part of the work has been to look into thepicking tool and to see if there are any possibilities to improve its function.The report presents two different proposals which I decided to call Robot 1 and Robot 2 andthey aim to address the problems arising in the purpose-built linear unit and the X-axislinearity problems. Robot 1 focuses on eliminating the problems that arise around therobot's X-axis, with such simple means as possible and without making excessive materialchanges.
Bootstrapvalidering av konfidensintervall för ett standardiserat mått för att jämföra behandlingsbenägenhet mellan sjukhus
In this Master thesis, microwave connections between circuit boards are constructed. The primary frequency band is the X-band (8-12 GHz). The purpose of the connections is to enable a more simple and cheaper way of mounting the circuit boards inside a container. The connections have been designed and evaluated, using different computer programs. A few prototypes have been built and measured.
Bokbloggen i de litterära kretsloppen : En litteratursociologisk analys
This thesis explores the position of book blogs in the literary system through Robert Escarpit's socio-literary model of the book market. Simultaneously the thesis serves as a test for Escarpit's theory: by actively applying his theory and model to a very new and contemporary actor on the book market I hoped to reach or confirm new insights into the usefulness and validity of Escarpit's work for contemporary socio-literary studies.Three book blogs were selected for the analysis and interviews were carried out with the authors. The interview questions were formulated specifically for the purpose of extracting the kind of information necessary for an analysis using Escarpit?s theory. As a complement to the interviews, statistics on the type of books reviewed on the blogs were also compiled.
Definition av stötdämpares fyllnadsgrad
Shock absorber units play a key role in establishing the driving dynamics and performance of automobiles. Öhlins Racing has manufactured high-tech automotive shock absorbers for over 30 years. Öhlins Racing?s advanced technology has contributed to over 200 world championships in automobile racing. Öhlin?s manufacturing process has long utilized automated fluid filling equipment during the final shock absorber unit assembly stage. The filling process consists of vacuum pumping the shock absorber unit and subsequent transfer of fluid. Vacuum pumping is necessary to remove residual air from the shock absorber unit prior to initiating the liquid filling stage. The presence of undesirable gases drastically compromises the performance of a shock absorber. The filling degree, defined as the final ratio of air to oil, is determined by the specific filling protocol as well as the specific equipment utilized.The current investigation aims to develop a viable technique to accurately determine residual air content in shock absorber units. If the filling degree can be appropriately quantified for a specific manufacturing process, then the air/oil ratio may be quantitatively related to shock absorber performance. The utilized measurement method must be completely integrated into the manufacturing process to guarantee shock absorber performance specifications according to the manufacturer?s standards. By utilizing the measurement method developed in this work, the manufacturing process, manufacturing equipment and product specifications can all be tailored to provide improved filling conditions.The developed measurement method provides accurate quantification of the filling degree under a wide range of processing conditions. The method establishes the relative quantity of air in the shock absorber unit by performing in-situ compressibility tests. The fill ratio can be controlled and varied by manipulating the vacuum pressure exerted during the filling process. Performance tests, however, indicate no correlation between filling degree and unit performance..
Spela för nöje eller spela för kunskap? : Lärares uppfattningar av IT-baserade matematikspel och dess konsekvenser på elevers kunskapsutveckling
Sveriges Radio stores their data in large archives which makes it hard to retrieve specific information. The sheer size of the archives makes retrieving information about a specific event difficult and causes a big problem. To solve this problem a more consistent use of metadata is needed. This resulted in an investigation about metadata and keyword genera-tion.The appointed task was to automatically generate keywords from transcribed radio shows. This included an investigation of which systems and algorithms that can be used to generate keywords, based on previous works.
Viral Facebook integration i mobilspelet Gravel
This thesis has treated a three-axis robot which task is to serve a larger test machine tomove the modules to be tested, from the storage to the test site. The robot is composed ofthree linear actuators; two standard components of ball screw type and a custom-builtactuator of trapezoidal type. The work has mainly focused on the custom-built device to seeif it could be replaced with a standard component. Part of the work has been to look into thepicking tool and to see if there are any possibilities to improve its function.The report presents two different proposals which I decided to call Robot 1 and Robot 2 andthey aim to address the problems arising in the purpose-built linear unit and the X-axislinearity problems. Robot 1 focuses on eliminating the problems that arise around therobot's X-axis, with such simple means as possible and without making excessive materialchanges.
INFÄSTNING AV LED-ARMATUR
The thesis was performed at the lighting company Zpecta AB. Zpecta needed to develop alternative attachment of their LED-luminaire Capella. Today Capella attaches in metal ceilings with four magnets. Zpecta got indications from their customers that there was a need for other attachments. The purpose is to determine the customer?s requirements and the interfaces that are considered for Capella.During the thesis, Capella was only on the market for testing and evaluation.The thesis was initiated to create a specification.
Design och konstruktion av laborationsutrustning till en kraftelektronikkurs
The purpose of this degree project was to build laboratory equipment for a new course in power electronics that starts this autumn 2010 at Uppsala University. The equipment is intended for student labs and it covers the most important areas of the course including rectifying, buck-/boost-converters and PWM-modulation. It is built as one sealed unit where all the electronics are built-in but visible and it has a connection board where students safely can connect the different circuits. The project has advanced from theoretical studies of circuit design, choosing of components and simulations to drawing the printed circuit board (PCB), soldering, case building, final testing and troubleshooting - basically most steps from an early idea to a final product. Measurements on the final product gave about the same results as the earlier simulations of the circuits and the result is overall satisfying..
Elcyklar och dess möjlighet till uppladdning under drift
Today?s environmental discussions have led to more progress in the different transportareas. To ride a bicycle is often one of the most efficient alternative when it comes totransport. An Electric bike is, and makes transportation more efficient than a regularbicycle. Electric bicycles do not affect the environment significantly and allows moreconvenient transportation than ordinary bicycles do.
Standardisering av funktionsblock for PLC
Automationscenter & Bråvalla Elteknik AB is a company that offers the market completed total solutions where the customer can operate and monitor their production from the terminal. In these total solutions they lack standard circuit which are developed by the company and which could manoeuvre/control/monitor controlled process objects. This report defines the work of developing the most common standard circuits.The report is initiated by a short theoretical part about PLC and the PLC system, with a connected terminal, which has been used. Thereafter, the turnout of the demands of specification is reported, after discussing with the supervisor in the course of the project. The report concludes with a disclosure of how the programming, the documentation and the testing have proceeded and a final discussion concerning the project and proposals on continuation.The result is a CD with the documentation of standard circuits and how they are implemented in a new project.
Geotermisk fjärrvärme i Gunsta
Gunsta is situated about 10 km east of Uppsala. Today there are plans to establish 1000 new households in Gunsta before year 2030. The required energy for heating houses and water would be distributed via a district heating system, which also includes 200 existing residences. The annual required energy, according to this study, would be 16.2 GWh with a maximal peak effect of 6.9 MW.
To meet this need, the study suggests a system with heat pumps to upgrade the 31?C water from a 1.8 kilometre deep borehole.
Parameterstudie av inneslutningsbildning och utvärdering av processföring för tillverkning av plastformsstål
This thesis has been performed at Uddeholms AB with the purpose to investigate theparameters affecting the formation of inclusions during the manufacturing of a low carbonmanganese-steel.A follow-up, steel and slag sampling and evaluations in microscope have been done for a totalof five heats.The results for each heat have been evaluated in relation to the theory from the literaturesurvey and suggestions for changes in the process to reduce the amount of inclusions whichhave a negative effect on the steel quality have been given.The project extends over a large process where many parameters affect the formation ofinclusions. However, a tendency that a higher addition of alloys seems to increase the totalamount of inclusions before and after the vacuum degassing is seen.The majority of the studied inclusions seem to approach the composition of the top slag aftervacuum degassing. Ladle glaze may cause the inclusions which had a different compositioncompared to that of the slag.A high or low ladleage together with a high argon flow during vacuum degassing seems todissolve particles from the refractory which later on get trapped inside the inclusions.The floatation for two heats has been studied where a short floatation seems to give a higheramount of inclusions in casted material.In machined material so called stringers were found. The main composition of those stringerswas pure alumina. Inclusions with a composition of pure alumina were not found in the liquidsteel, thus the pure alumina inclusions must be formed during the casting.
Tonfrekvensspårledning : S-förbindningens funktion och dimensionering av alternativa material i förbindningen
Spårledning används inom järnvägen för att lokalisera var tåg befinner sig. Detta examensarbete behandlar en modell av tonfrekvensspårledningar från Alstom. Teoridelen behandlar de båda modellerna DTC ? 921 och DTC- 24 medan uträkningarna enbart behandlar den tidigare. Tonfrekvensspårledningar separeras med elektroniska skarvar genom förbindningar i spåret.
Grafisk skärm för inbyggda system : Framtagning av en prototyp
A degree project has been carried out at Motion Control, Västerås. The degreeproject ?Grafisk Skärm för Inbyggda System? have developed a first prototype of anembedded system with a display, a graphical user interface with touchscreen andpossibilities to communicate with external units.The work initiated with surveys of critical components. A technical specification forthe desired end product was developed. With the technical specification as support,design specifications for hardware and firmware were developed.After the specifications were done, a circuit diagram was developed and a circuitboard was made.
Planering av produktionsflöden. Vad kan påverkas i projekteringsfasen?
Göteborg Energi AB är ett bolag med höga ambitioner att säkerställa ett stabilt distributionsnät för sina kunder. Med ett säkerställande följer åtgärder i form av beräkningar för komponenter som transformatorer av olika märkeffekt, hög- och lågspänningssäkringar och andra kritiska skyddsanordningar som t.ex. reläskydd. Vid ett flertal tillfällen under de senaste åren har det uppmärksammats en problematik där ett fel i lågspänningsnätet har löst ut anslutande transformator. Felet har grundat sig en svag selektivitet mellan transformatorsäkring och lågspänningssäkring.