Fraunhofer Chalmers Research Centre for Industrial Mathematics
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Logistical efficiency in comparison when outsourcing from Asia versus outsourcing from Europe A case study on a shoe developing company
No full textIcebug AB’s headquarter is located near Gothenburg in a town named Jonsered. The company has 26 employees and the net sales of 2018 were around 157,4 million SEK. Main areas of conducted business are designing, developing and selling outdoor shoes for extreme weather conditions.
The purpose of this case study was to evaluate the difference in logistical efficiency based on outsourcing Icebug AB’s production of a specific product from an Estonian vendor versus outsourcing from a Vietnamese vendor. The current state (Vietnamese case) is based on data from 2018. The prospective state (Estonian case) is based on data from 2018 and feedback from the Estonian vendor.
To be able to validate the data in this study, open-ended cross sectional interviews with multiple departments were conducted and multiple documents were overviewed. Furthermore, the processed data was reviewed, compared and followed up with informal interviews. Procedures such as checking transcripts for mistakes and comparing findings from multiple sources were implemented.
The logistical efficiency was limited by variables such as total cost, tied up capital, customer service, delivery flexibility, environmental impact and time to market. The supply chain was delineated with the boat freight from the vendors to the main storage facility in Gothenburg.
To examine the purpose, the current state (Vietnamese case) and prospective state (Estonian case) were compared. The difference in outsourcing the production of product a specific from Estonia versus outsourcing from Vietnam were: The total cost will decrease with 30%, the overall customer service will improve, the overall tied up capital will be minimized, the overall environmental impact will decrease, and the delivery flexibility will increase.
This study concluded, on the basis of the empirical evidence and evaluated factors, that Icebug AB should change the outsourcing of the production of the specific product to Estonia
Undersökning av döende stjärnor: Massförlust och molekyler för stjärnor på den asymptotiska jättegrenen
No full textThe study aims to investigate the mass outflow from evolved stars. Emission lines
from nine stars, observed under the project DEATHSTAR, were studied. The gasmass-
loss rates were approximated using a simplified formula based on the rotational
emission lines of 12CO. Furthermore, the project aims to determine the molecular
composition of two of the nine stars, W Hya and R For. The calculated gas-mass-loss
rates varied from 10−7 to 10−5M yr−1. The dust-mass and dust-mass-loss rate calculations
were only attempted regarding the star W Hya, though no dust-mass and
dust-mass-loss could be determined from the data. The observed emission spectra
from W Hya and R For contained at least 16 and 17 molecular emission lines respectively.
The outflow of W Hya is dominated by oxygen based molecules, while
the outflow of R For contains carbon based molecules. Finally, the emission lines
from 12CO for several stars show evidence of asymmetric envelopes. The obtained
profile for R Hya hints at multiple velocity components and might warrant a more
in-depth investigation in the future
Information and Material Coordination for Projects Understanding and Improving the Supply Chain Management for Prototype Production in an Electronics Company
No full textVeoneer is an automotive safety development company with development and production
spread over 13 countries. The operations in Sweden consists of a production plant in Vårgårda
and four engineering plants located in Linköping, Gothenburg, Stockholm and Skellefteå. The
plant in Vårgårda is mainly focused on serial production but also responsible for manufacturing
prototypes that are in the middle or late stages of development. As most of the prototypes are
produced on serial production lines, tight coordination between project members, that are
responsible for the prototypes, and the serial production team is necessary in order to have
efficient and functioning operations. Due to capacity constraints and conflicts of interest
between serial- and prototype production, it is important to utilize the time given from serial
production in order for Veoneer to supply for the demand for prototypes. Thereby, preparations
prior to production runs are essential to prevent the production lines from standing due to lack
of material or information. The purpose of this thesis was thus to understand, map and
document the information and material flow for prototypes at Veoneer’s production plant in
Vårgårda, and further develop improvements related to the prototype supply chain
management.
To fulfill the purpose, empirical data of the current situation at Veoneer was collected by
observing processes, interviewing people and measurement studies. In order to understand the
process flow, a value stream map was constructed together with a process overview. The
empirical data was then analyzed to identify problem areas related to the supply chain
management for prototypes. The problem area created a basis for which the improvement
suggestions and implementations were built upon. The suggestions included investments in
equipment to facilitate tasks related to material handling and thereby reducing the amount of
time spent on non-value adding activities. In addition, emphasis was put on information sharing
and process improvement related to prototype production.
Through a cost-effect matrix for evaluating improvements it was shown that Veoneer has the
opportunity to proceed with the ‘low hanging fruit’ that requires low effort in relation to the
benefits that can be drawn. In conclusion, the significant amount of time spent on ensuring
material availability is reduced by the implementations made and together with the proposed
suggestions, the information and material flow for prototypes can be improved
Maximum Likelihood calibration of the Vasicek model to the Swedish interest rate market
No full textSedan 2015 har räntan i Sverige varit negativ vilket historiskt sett är ett väldigt ovanligt fenomen. Därav kan de flesta matematiska räntemodeller ej modellera negativa räntevärden. Denna rapport ämnar undersöka hur den svenska räntan kan modelleras i dagens ränteklimat.
Detta kommer ske via att applicera Vasiceks modell till svenska statsskuldsväxlar. Vasiceks modell blev fokus för rapporten tack vare det faktum att det är en Gaussisk process som fångar den långsiktiga räntan och kan därför i kvalitativa termer anses modellera svenska statsobligationer. Beräkningarna gentemot modellen gjordes via maximum likelihood-metoden. Via detta upptäcktes att parametern som ämnar mäta hastigheten till den långsiktiga räntan, α, ej var väntevärdesriktig för värden nära noll. När detta togs i beaktande visade sig Vasiceks modell resultera i en relativt bra estimering i jämförelse med den svenska avkastningskurvan. Dock resulterade detta i en modell med negativ α-parameter, vilket överskred modellens tendens att gå mot den långsiktiga räntan. Istället är väntevärdet av räntan en evigt stigande funktion. Från detta kan det argumenteras att modellen inte fångar konceptet kring långsiktiga räntenivåer vilket gör modellen icke-önskvärd för tidsperioder längre än tio år.
Vidare ämnar denna rapport prissätta räntederivat via Vasiceks modell. Specifikt så testas caps och floors prissättas via Blacks modell vilket i sin tur är beroende av framtidsräntan. Dock uppmärksammades att Blacks modell inte tillåter negativa räntevärden då detta ger logaritmen av negativa värden. Istället presenteras en prissättningsmetod av dessa derivat via Monte Carlo simuleringar vilket i sin tur gav önskvärda resultat för priset på caps/floors. Från detta kan en slutsats dras att prissättning kan göras av dessa derivat för den relevanta tidsperioden fem till tio år.
Nyckelord: statsobligationer,avkastningskurva, Vasicek-modellen, maximumlikelihood-metoden, korttidsränta, caps och floors
Den gröna autonoma staden - Autonoma fordons potentiella hälsofrämjande effekter
No full textSyftet med denna rapport är att belysa vikten av att planera för de autonoma fordonens ankomst och hur detta kan göras för att främja folkhälsan i städer. Vidare redovisas potentiella hälsoeffekter samt ekonomiska besparingar av att implementera autonoma fordon i en stad. Detta med inriktning mot psykisk och fysisk hälsa, luftkvalitet samt trafiksäkerhet. Beräkningarna grundas i den nyvunna yta som kan tänkas frigöras när autonoma fordonens implementeras och som kan öppna upp möjligheter för nya grönstråk och parker.
För att sammanställa arbetet har litteraturstudier, intervjuer samt insamling av data genomförts. Ett scenario om ett optimalt utfall för autonoma fordon i staden antas, för att påvisa vikten av god planering och styrning.
Konkret visar resultatet av studien en möjlig ekonomisk besparing på 494 000 000 SEK per år, vilket är en grov uppskattning för scenariot inom valt område i Göteborg. Detta kan ses som en indikator på att det finns möjligheter att påverka folkhälsan samt att göra besparingar genom den nya tekniken och implementering av mer grönyta i en stad
Movable Automation for Low Volume and High Mix Production – Benefits and Barriers
No full textThe current trends of mass customization along with digitalization of the industry are increasing the demands on companies to produce low volume series with high variation. Small and medium sized enterprises generally don’t have the financial power to invest in the latest production technology, nor is it plausible to dedicate machines for a few products when these subcontractors’ product range is ever changing. However, the rise of movable automation may be a means for these companies to automate their low volume high mix production. This thesis aims to evaluate the operational effects of this movable automation, but also to find the barriers of utilizing it at three case companies. The movable automation in this study is movable industrial robots with a fenceless security system.
The results show that the case companies have experienced problems with utilizing the robots in a favorable way. Therefore, direct operational effects were difficult to find, but the robot is deemed to have high potential at these companies, decreasing production costs, increasing quality, making the work environment better and increasing productivity. However, in order to utilize the potential that the robot provides, there are barriers that the companies need to overcome. The main barrier being the studied companies’ lack of resources in the form of time and competence. This leads to difficulties of adapting their products for automation, as well as designing and producing grippers. Hence, the robot has not been able to cope with the low volume high mix production of these companies as intended. With enough resources spent on developing the technical solution, it is believed that the companies will be able to utilize the potential of movable automation, thus increasing their competitiveness
