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QC 351 A7 no. 48 / New materials of low thermal expansion are finding wide application. The expansion coefficient (a) is a function of temperature, and this function must be known for each material before its applicability can be assessed. A novel method for determining a, which is at once precise and easily implemented, has been devised. It is based on the dependence of mode frequencies in a Fabry-Perot interferometer on the mirror separation. The expansion sample is formed into an interferometer spacer with ends polished flat and parallel. Spherical mirrors are optically contacted to the ends, forming a confocal interferometer. The assembly is maintained at controlled temperatures in an environmental chamber. The two lowest -order transverse modes are probed by variable -frequency sidebands derived from a 633 -nm He- Ne laser by amplitude modulation. A change in sample temperature AT causes a change in interferometer length AL, which shifts the resonance frequencies by Av. Then a = (1 /AT) (AL /L) _ - (1 /AT)(iv /v). Thus, a can be measured with precision limited ultimately by the stability of the source laser, in practice 1:109 with presently available commercial lasers. For a sample of Owens -Illinois Cer -Vit, a has been measured at 10 temperatures in the range 3.0 to 32.4 °C, with a mean error of 2 x10-9 and a maximum error of 3 x10 -9. For a sample of Corning ULE silica, a has been measured at six temperatures in the same range, with a mean error of <1 x10 -9 and a maximum error of <1.3 x10 -9.

The topic of my work is about how the product is getting from designers to final customer. As logistic is a collection of many different activities we talk about production, warehousing, transport and final presentation to the customer. But nowadys logistics is not only about material flow but about the information flow as well. That is why we cannot forget to mantion the communication with the client and getting his response.

Hard-burnt magnesium oxide (MgO) has been successfully used in large volume concrete, mainly dam construction in China, for thermal shrinkage reduction since the 1970’s. At ~4% addition to the cement by weight, it is much simpler than conventional shrinkage measures and in particular, reduces the quantity of crack control reinforcement used. The mechanism is similar to conventional ettringite-based and lime-based expansive admixture relying on their expansion to offset concrete shrinkage. In other words, the tensile stresses induced by concrete shrinkage are offset by the compressive stresses induced by MgO expansion under a restrained condition so that shrinkage and cracking can be reduced. While there are technical specifications in China for this application, the production of MgO is not robust enough to produce specified MgOs, and thus specific performance cannot be specified or guaranteed. In addition, there has been very little rigorous scientific research work in the literature on the performance mechanisms and controlling variables. These issues have hindered the application of the unique designable expansion characteristics of MgO and have limited the application in thermal shrinkage reduction. Hence, this PhD study aims to investigate the expansive characteristics of a number of commercially available MgOs used as an additive and evaluate their shrinkage reduction in cement and concrete. This work also presents a literature review of MgOs, particularly from Chinese sources, and a thorough evaluation of the expansion characteristics and shrinkage reduction capabilities of MgOs with different reactivities in both cement paste and concrete. To this end, four different reactivity MgOs obtained from seawater, brine and magnesite were tested. First, cement paste and concrete prisms - both cured in water - were used for correlating MgO reactivities with expansion characteristics under unrestrained and restrained conditions. The changes in length in cement paste and concrete prisms showed that the MgO expansion rate and magnitude increased with MgO content and reactivity as well as water content. Provision of restraint in prisms both decreased the magnitude and rate of expansion. Highly reactive MgOs showed higher early age expansion and plateaued in a relatively short period while less reactive MgOs exhibited delayed expansion. Temperature increase accelerated all MgOs hydration activation. In particular, less reactive MgOs displayed rapid expansion at an early age instead of delayed expansion. With regards to unrestrained compressive strength development, it was found that the higher the MgO expansion, the greater the compressive strength reduction. Microstructural analyses confirmed the existence of MgO hydration product brucite which contributed to the expansion. While the brucite quantity increased in cement paste systems, it had an insignificant influence on cement paste pH and thus potential reinforcement corrosion resistance. Similar expansion characteristic was found in the PC-Slag cement pastes containing different reactivities of MgOs as compared to that of PC cement paste except that the PC-Slag cement pastes displayed a slightly higher expansion than PC cement at an early age but lower ultimate expansion. One high reactivity MgO (MgO-N50) and one medium reactivity MgO (MgO-92/200), with distinct expansion characteristics, were selected for evaluating the shrinkage reduction performance of cement paste in autogenous and drying curing conditions. Autogenous shrinkage of unrestrained cement paste prisms was measured using laser sensors and length comparator at an early age (< 24 hours) and long-term respectively. The results showed that autogenous shrinkage in the cement paste containing the MgOs was reduced and further decreased with MgO reactivity, content, as well as water content. Compared to PC, the slower strength development in PC-Slag cement resulted in smaller autogenous shrinkage reduction. Drying shrinkage reduction was observed at an early age in both PC and PC-Slag unrestrained cement paste containing the MgOs at water-to-bonder (w/b) ratio of 0.5, although the long-term shrinkage was higher than the control. To further investigate the benefit of early age MgO expansion in drying shrinkage reduction, the final part of the study focused on restrained concrete specimens using the restrained ring test. The results showed that drying shrinkage was reduced in PC concrete with the addition of the highly reactive MgO-N50 when the w/b ratio was increased from 0.40 and 0.50. On the contrary, drying shrinkage reduction was not observed in the PC concrete with the less reactive MgO-92/200. Neither MgOs in PC-Slag concrete showed drying shrinkage reduction. The results reaffirmed the earlier findings that MgO expansion is dependent on strength development. The combination of pre-compressive stresses, delay in tensile stress development and smaller modulus of elasticity of MgO concrete contributed to a lower stresses-to-strength ratio and thus higher resistance to cracking caused by drying shrinkage. From an engineering point of view, the high reactivity MgO-N50 characterised by early age expansion can be used for reducing concrete autogenous shrinkage as it is used for drying shrinkage effect. The less reactive MgO-92/200 with delayed expansion can be utilised in mass concrete to address thermal shrinkage.

Syfte: Denna studie fokuserar på ett företag, Gavle Marknadskommunikation. Syftet med uppsatsen är att undersöka hur och varför företaget expanderade till flera nya regioner. Då företaget senare gick i konkurs och därefter nybildades så ämnar jag undersöka om expansionen hade någonting med konkursen att göra. Detta för att kunna utreda vilka risker som togs i samband med expansionen, samt ge exempel på vad man bör tänka på när man skall expandera sin verksamhet. Dessutom skall jag utreda vad som kunde ha gjorts för att förhindra konkursen.

Purpose/ aim: The aim is to examine if IKEA expand too fast. We try to find answers to this problem. This is a huge problem to IKEA and other large-scale companies which plan to expand in the world. Design/methodology/approach: Data on customers’ feelings has been collected through questionnaires. The analysis includes a description of the sample and statistic test. After the test, the relationship between price and quality will be found. Findings: The analysis showed that the expansion of IKEA is fast enough to affect the quality of the products. There is a positive relationship between the quality and price. The rule is that the higher the price the better the quality. The data collected from the questionnaires shows that people think that the quality of IKEA’s products has decreased. In the analysis, the details are showed. What happened, and why did it  happen? From this we suggest that IKEA should slow down the steps to expansion and pay more attention to the quality of the products. Originality/ value: The topic about IKEA’s expansion is a totally new area, which hasn’t been researched upon before. Most people think IKEA is a miracle and they always hope IKEA will build more stores in the world, but with this we disagree. Based on these findings we would argue that IKEA should slow down the steps to expansion and pay more attention to the quality of the products. This study has value for all the large-scale companies that want to find a way to analyze if a company expands too fast.

Detta examensarbete har genomförts på ABB Power Products/Instrument Transformers i Ludvika. Syftet med arbetet har varit att undersöka temperaturexpansionen för en isolerande olja som använd i produkten Capacitor Voltage Transformer (CVT). Oljans egen temperatur­expansionskoefficient                          var redan känd, men arbetets syfte var att bestämma en Brutto­temperaturexpansionskoefficient, med andra ord undersöka hur mycket de ingående komponenterna i en CVT påverkar den totala volymexpansionen inuti enheten. För att bestämma bruttotemperaturexpansionskoefficienten har ett prov i klimatkammare utförts. Provet bestod av två aluminiumkärl vardera med ett monterat mätrör. Det ena kärlet fylldes med olja och det andra kärlet med olja och kondensatorinnehåll motsvarande inne­hållet i en CVT. Provobjekten utsattes sedan för en bestämd tid i temperaturer från -60°C till 65°C med intervall om 10°C. Under denna tid utfördes ett antal mätningar av oljevolymen i de båda provobjekten. Dessa mätningar användes sedan tillsammans med ett några korrektions­faktorer för att beräkna temperaturexpansionskoefficienten för både oljan (enbart för kontroll­erande syfte) och kondensatorinnehållet. Tillsammans ger dessa bruttotemperaturexpansions­koefficienten för alla möjliga volymkombinationer. Resultatet från provet har sedan analyserats och visualiserats i form av tabeller och diagram. Efter det beräknades temperaturexpansionskoefficient för oljan samt  för kondensator­innehållet vid olika temperaturer. Utifrån dessa värden beräknades de genomsnittliga temperatur­­expansionskoefficienterna för temperaturintervallet och slutligen angavs en formel för att bestämma bruttotemperaturexpansionskoefficienten för olika procentuella fördelningar mellan olja och kondensatorinnehåll. Till sist drogs slutsatser utifrånfrån resultatet. / This bachelor thesis was carried out at ABB Power Products/Instrument Transformers in Ludvika. The purpose of the work has been to examine the thermal expansion for an isolating oil that is used in the product Capacitor Voltage Transformer (CVT). The oil’s own expansion coefficient                          was already known, but the purpose of the work was to determine a gross thermal expansion coefficient, with other words to examine the amount of influense the other componets had on the volume expansion inside the unit. To decide the gross thermal expansion coefficient a test has been carried out in a climat chamer. To performe the test two aluminum tanks, each with a measurement tube mounted on the top were used. One of the tanks was filled with oil and the other one was filled with oil and capacitor contents corresponding tio the contents in a CVT. The two test objects were then exposed to temperatures reaching from -60°C to 65°C in steps of 10°C. During this time a number of volume measurements were performed on the two test objects. These measure­ments together with a few correction parameters were used to decide the thermal expansion coefficient for both the oil (only for control purpose) and the capacitor contents. Together these two gives the gross thermal expansion coefficient for all posible volume combinations. The results from the tests has been analised and visualised in the form of tables an diagrams. After that the thermal expansion coefficient for the oil and the capacitorcontents, for different temperatures was calculated. Bult on those calculations the avarege thermal expansion coeff­icient for the temperatureintervals was calculated, and finaly an modle for calculating the gross thermal expansion coefficient was created. At the end conclusions were drawn from the results.

Vårt examensarbete i informatik är utfört på ett producerande företag som expanderat och därför sett behov av att förändra sin organisation. Ägarna upplever att personalplanering och tillverkningsplanering är alltför tidskrävande och de hinner inte med viktiga arbetsuppgifter som marknadsföring och företagsutveckling.Examensarbetet har innefattat teoristudier, en analys av företagets verksamhet samt utformning av förändringsförslag för att förbättra företagets organisation. Våra litteraturstudier har bestått av inläsning av teorier om problem som kan uppstå i expanderande företag samt datainsamling genom intervjuer av företagets ägare och några av de anställda. Detta har legat till grund för den verksamhetsanalys vi genomfört med hjälp av delar ur metoden FA/SIM. Denna analys ligger till grund för de förändringsförslag som har arbetats fram.I analysen har problem som rör följande fyra aktiviteter identifierats. - Arbetsledning - Planering - Tillverkning - VaruleveransDe åtgärdsförslag vi anser viktigast att genomföra för att effektivisera och underlätta arbetssituationen för ägare och anställda är att börja registrera ordrar dagligen och införa rutiner för att registrera produktion och lagerhållning. Ytterligare åtgärder är att anställa kvalificerad personal på kontoret samt utbilda fler i personalen i att köra lackeringen.Vi kan konstatera att företagets övergripande problem till stor del orsakas av att organisationen inte anpassats till företagets expansion. Det är vanligt att insikt om detta kommer först när problemen börjar kännas oöverstigliga.