Sök:

Sökresultat:

187 Uppsatser om Differential Geometry - Sida 9 av 13

Flexibla fixturer i bearbetande maskiner

This thesis was conducted at Linköping University and Saab Aerostructures DPS, Linköping, and focuses on the possibilities of flexible fixturing in machining applications. The thesis is part of the research project "Koofix", which is collaboration between Linköping University and a number of companies.The thesis is aimed towards small batch production which, for Saab Aerostructures DPS, means diverse part geometry and that parts are manufactured in very small numbers, sometimes just one piece. The result of this is that expensive dedicated fixtures are made for most parts. By introducing more flexible fixturing methods to this kind of production the cost of fixtures and tooling will be reduced, and make the production more efficient.New flexible fixturing methods has been presented and evaluated through the thesis, which has resulted in three different concepts. These concepts have been the result of literature screening and study of current manufacturing process at Saab Aerostructures DPS.

Inverkan av betessläpp på celltal och mjölkkvalitet hos mjölkkor :

In Sweden regulations stipulates that dairy cows are kept on pasture, or given the opportunity to spend time outside during a coherent period of between two to four months, depending on region. The transition out to pasture is a big change from the winter period in the stable, especially for the modern high yielding dairy cows. The let out to pasture includes a change in feed, environment, and new routines. There are indications that the milk somatic cell count (SCC) rises in a peak shortly after the let out. The purpose of this study was to see if peaks in the SCC could be observed after the let out, and to study the contribution of inflammatory cells (neutrophils) and if the milk composition are affected. The study included 35 cows that were kept in stable during the winter.

Immunhistokemisk undersökning av paraffinbäddade celler från pleuravätska som kompletterande underlag för diagnos av cancermetastaser

Background. Immunohistochemistry is a useful method in the differential diagnosis between pleural mesotheliomas and metastatic adenocarcinomas in the pleura. Cytokeratin 20 and 7 have been used successfully as markers in studies determining primary location of adenocarcinomas from metastases. The current study is a complementary research of archived paraffininbedded material of cases with cancer origin. This study contributes a bigger statistical material that may facilitate the search for unknown primary site of adenocarcinoma by identification of metastatic cells in the pleura.Methods.

CFD simulering av en fyrtakts Otto motorcykel motor

This thesis deals with the numerical 3D simulation of a four stroke, spark-ignited, internalcombustion engine, which is mounted on a high performance motorcycle. The work, carried outin collaboration with Politecnico di Milano and MV Agusta, focuses on the simulation of theintake, compression and expansion stroke, including combustion simulation, using an opensource CFD code.Simulation of internal combustion engines offers a great challenge in the field of CFD research.Moving boundaries of the solution domain, caused by the motion of the piston and valves, leadsto deformation of the computational grid, with decreasing quality of the solution as result. Basedon this, a previously developed mesh motion strategy was employed where a number of meshesare used to cover the whole simulation cycle. Within each mesh interval the internal cell pointsof the mesh are moved to account for the boundary motion of the piston and valves. This strategywas previously applied to simplified geometries as well as real engine geometries.

Kvalitetsprocesser och mätning av pinnfräsar : ? Empirisk studie av produktionsmätutrustning vid frästillverkning

This master thesis investigates quality procedures and measuring of solid carbide end mills, with the main focus on measuring equipment. The thesis has been written in collaboration with a special production department for solid carbide end mills at Sandvik Coromant in Gimo. The department?s needs and constraints have been the foundation of the project and the main research question is: how to measure end mills in order to ensure good quality of the produced end mills. The project has contained both a theoretical study consisting of a literature review and practical studies in the workshop with the objective to identify an end mill?s main parameters and the relationship between an end mill?s geometry and the manufacturing processes.

Ett nytt pedagogiskt material! : 4DFrame, hur kan man arbeta praktiskt med det?

The objective of this study is to investigate a new pedagogical material called 4DFrame, how it is experienced by informants and how suitable it is in education - in particular mathematics. Socioculturalperspective has a central role in this study when students are given opportunities for linguistic and social interaction during the experiment with the new pedagogical material. The methodology for this study has been visits, interviews, and observations. The study reveals that there are different views on the didactic potential for mathematics of the new teaching material, though no conclusions can be drawn regarding whether this material is more or less suitable in teaching since no research have been found that compares this with other pedagogical materials. Both national and international studies show the need to find alternative and better ways to make mathematic education meaningful.

Användning av CAD-data vid NC-programmering

The degree project is performed at Metso Kamfab. The production is aimed on machines everything from handling of fiber to paper pulp. Metso Fiber and Kamfab are using Pro/Engineer for design and blueprint production. The processing department types the NC-programs in notepad on the basis of the blueprints, the CAD-dates that already is there are not used. The aim with the work is to study if Kamfab can use CAM-system for processing and production of programs for their NC-machines.

Undersökning av retrobulbärområdet på hund med hjälp av ultraljud :

This study was performed in order to investigate the difficulty in diagnosing retrobulbar disease with ultrasound. A retrospective study was accomplished to investigate the use of ultrasound in patients with suspected retrobulbar problems, and how often the examination is diagnostic. The computer based patient files, at the University of Agricultural Science in Uppsala, were searched for dogs with suspected retrobulbar disease. During 1999-01-01-2004-04-14, 14 patients fulfilling the search criteria were found. The patient records were studied, and the written reports from the ultrasound examinations were compared with the printed pictures from the examinations.

Konceptstudie av en kompakt Picker robot

Picker robots are often mounted close to each other above a conveyor belt. To be able topack robots even closer, it is desirable to reduce the footprint of the robot?s base. One way toachieve this is to skew the arms of the robot which makes it possible to move them closer toeach other.This Master Thesis has been carried out at ABB Corporate Research. The purpose is toevaluate the benefits and drawbacks for the idea of making today?s Picker robot morecompact by skewing the arms.

Determination of anthelmintic resistance of Haemonchus contortus to three classes of anthelmintics in a Kenyan sheep flock based on results from faecal egg count reduction test

Haemonchus contortus is the most important bloodsucking gastrointestinal nematode in small ruminants worldwide. It is often controlled by anthelmintics. Even though other methods to control are available, the most efficient way to treat an animal with clinically manifested haemonchosis is to use one of the available broad spectrum anthelmintics: benzimidazoles (BZ), macrocyclic lactones (ML) or imidothiazoles-tetrahydropyromidines or the narrow spectrum drugs salisylanilides or nitrophenols. Anthelmintic resistance (AR) against all groups of anthelmintics in nematode parasites has been reported from many countries, and even multiple AR has been observed. In this study I have investigated the resistance levels to all major classes of broad spectrum anthelmintics in a naturally infected flock of sheep of Red Maasai sheep (RM), Dorper sheep (D) and their offsprings on a research farm in Kenya.

Förbättrat råvaruutnyttjande vid kvalitets-sortering av timmer : utvärdering av analysprogrammet Stockholmen för automatiserad timmersortering i dimensions- och kvalitetsklasser hos BARO WOOD AB

The aim of this thesis was to analyse BARO WOOD AB:s timber measuring and quality sorting and to evaluate the analyse program Stockholmen. The purpose was to get a better understanding for the quality sorting made at BARO WOOD AB today, analyse differences in center board quality from logs with a good quality and logs with a bad quality, suggest new sorting criterias developed from analyses made with Stockholmen and to evaluate the program Stockholmen. All analyses are based on data gathered in a test sawing made at BARO WOOD AB in June and July 2002. The test sawing was made on four different diameter classes and every diameter class consisted out of A or M-grade logs, with a better quality, and B-grade logs with a lesser quality. The logs where sorted out with BARO WOOD AB:s existing quality criterias.

Köpbeteende ? Den svenska kundens benägenhet att handla ekologisk bomull

Syftet med vår uppsats var att undersöka vilken kunskap den svenska konsumenten har om ekologisk bomull samt om de handlar kläder av ekologisk bomull. Vi genomförde en enkätstudie med både kvalitativa och kvantitativa inslag. Enkätundersökningen utfördes i centrala Göteborg vid fem tillfällen under april. Både män och kvinnor mellan 20-60 år tillfrågades. Vid analysen av enkäterna valde vi att ta ut statistik i diagram och tabeller.

Stenmaterial vid asfalttillverkning

Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.

Tegelhus I Klippan, Göteborg

Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.

Industrialiserat byggande - en nulägesbeskrivning

Denna rapport beskriver arbetet med utvecklingen av en ny modell för kaplanturbiner. Utvecklingen bygger på två kopplade differentialekvationer som under arbetets gång anpassats och implementerats i turbinmodellen.Modellen beskriver hur vattenflöde och turbinmoment påverkas av avvikelsen från den optimala kombineringskurvan för vinklarna på turbinens ledskena och löphjul, och är anpassad för ett referensaggregat med tillgängliga provdata. Även övriga enheter i vattenkraftaggregatet modelleras och sätts samman med frekvensregulator och elnät för att simulera aggregatets reglerstabilitet i önätsdrift.Verifieringen av turbinmodellen sker genom försök att återskapa de befintliga verkningsgradskurvorna med hjälp av modellen. Resultatet visar en god följning av de verkliga kurvformerna, dock med något lägre maximal verkningsgrad.Verifieringen av önätmodellen sker genom att prova stabiliteten i nätfrekvens och turbineffekt vid stegpålastningar. Resultatet ger en stabilare reglerstabilitet än i verkligheten, men uppfyller ändå förväntningarna på en fungerande modell.This report describes the development of a new kaplan turbine model.

<- Föregående sida 9 Nästa sida ->