Fraunhofer Chalmers Research Centre for Industrial Mathematics
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Reparationer på parkeringsdäck av armerad betong - Inventering av åldrade betongreparationer
No full text
Optimization of internal material flow - A case study at a Swedish manufacturing company
No full textStudien genomfördes på Swedish Match som har ungefär 5400 anställda och en omsättning på omkring 16 miljarder kronor. Företaget utvecklar, tillverkar och säljer tobaksprodukter. I Sverige återfinns två fabriker som tillverkar snus lokaliserade i Göteborg och Kungälv, där studien genomfördes i den sistnämnda fabriken. Omfattningen av studerat materialflöde avgränsades från godsmottagning till första produktionsstation samt från sista förädlingsprocess till utlastning. Syftet med studien var att ta fram förslag på hur det interna materialflödet kan effektiviseras. En ökning av produktionsvolym i kombination med hög produktmix har skapat platsbrist och ineffektiv materialhantering.
En litteraturstudie genomfördes inom områdena ledtid, lean produktion, produktionsstyrning, lager, materialstyrning, informationssystem för logistik samt logistik och IT. Datainsamling genomfördes genom intervjuer, observationer och processkartläggning. Utifrån insamlad information gjordes en nulägesbeskrivning som låg till grund för vidare analys och framtagning av förbättringsförslag. Denna innehöll fabrikslayout, lager, material- och informationsflöden, affärssystem och arbetsrutiner. Problemområden identifierades utifrån nulägesbeskrivningen och genom att använda verktyg som bland annat fiskbensdiagram kunde problemen och orsakerna till varför de uppstått analyseras. Problemområdena som uppmärksammats utifrån nulägesbeskrivningen och analyserats är materialhantering vid stora kvantiteter inkommande material, platsbrist i lager, långa transportsträckor för ZYN-artiklar samt kommunikations- och informationsflöden.
För att förbättra materialflödet i fabriken rekommenderas följande åtgärder: införande av slottider för inleveranser, basera inköp på förbrukning genom att använda dragande system, använda svensk leverantör av ask och lock till ZYN-produkter, integrera packning och etikettering i samma produktionsavsnitt samt utöka användningen av visuell styrning
Nano-optical Control of Chiral Photochemistry
No full textMany active compounds in pharmaceutical drugs are chiral, meaning that they
consist of molecular forms that cannot be superimposed into one another. The
different chiral forms are called enantiomers, and the pharmaceutical properties of
the different enantiomers can vary extensively. One of the major challenges within
the pharmaceutical industry when it comes to cost-effective manufacturing of safe
and effective pharmaceutical drugs is therefore to produce medicines consisting of
only one enantiomer, so called enantiopure compounds. Today, the chiral synthesis
of enantiopure compounds is mainly done by using complicated and expensive
methods within advanced organic chemistry. This thesis proposes a new physical
approach to chiral synthesis, which is both cheaper and less complicated compared
to the methods used today.
In order to test this approach, a model system based on the chiral photochemical
reaction of a model prochiral molecular photoswitch is used. The photoswitch is a
derivative of dithienylethene (DTE) called DTE-1, and it undergoes a reversible phototransformation
between an achiral and a chiral form commonly called the ’open’
and ’closed’ forms respectively. The two enantiomers in the closed form have a different
ability for absorbing left and right circularly polarized light (LCP and RCP
light), but this difference is most often not enough to create a considerable enantiomeric
excess of one or the other enantiomers by only illuminating them with LCP
or RCP light. Optical plasmonic nanoantennas, which are antennas that can manipulate
(i.e. receive and transmit, modify its polarization etc.) light on the nanoscale,
are designed and fabricated to have an enhanced chiral optical near-field. Experimental
characterization methods involving circular dichroism (CD) spectroscopy
has together with numerical simulations indicated that the fabricated nanoantennas
have the desired properties.
By placing the DTE-1 molecules in a close proximity of the nanoantennas and illuminating
with non-polarized light of the wavelengths that trigger the photochemical
reaction, the aim is for the enhanced near-field to induce an enantiomeric excess
at phototransformation. According to the results presented in this thesis, this is
achieved for two samples made up of spiral shaped aluminium nanoantennas. Reproducibility
of both the fabrication and chiral synthesis was not possible to prove
within the time frame of this thesis, and is something that needs to be considered
in order to draw final conclusions. Even though there still is an extensive amount of
work needed before the proposed approach could be used within the pharmaceutical
drug development process, this thesis paves the way towards this vision
Tekniker för kommunikation mellan arbetsfordon: utvärdering av DSRC samt C-V2X
No full textIn a transport system where vehicles are on their way of becoming autonomous,
wireless transmission can be a key factor for success. Information is being shared
between vehicles as well as with their surroundings. CPAC Systems in Mölndal,
Sweden, are using intervehicular communication as part of their development of
control systems for the automotive industry. In the present project, technologies for
data transmission are evaluated based on certain criteria, such as latency, range and
data rate. The project is a prestudy that lays a foundation for further testing. The
evaluated technologies are Dedicated Short Range Communications (DSRC) and
Cellular Vehicle-To-Everything (C-V2X). DSRC is recommended when fast data
transfer is required and safety has high priority. C-V2X is recommended for data
transfer with long distance between units
Understanding the Requirements of Forecast in Demand Driven Material Requirements Planning
No full textIn a world with high variations and uncertainties, the traditional material requirement planning is no longer sufficient. This planning system relies on fixed schedules and do not consider deviations. Therefore, a new demand driven material requirement planning (DDMRP) methodology has been introduced. This method enables companies to control variability using buffer levels to achieve high service level and low inventory costs. That said, companies are currently facing numbers of internal and external challenges when using this new method. The challenges are divided into four areas; external supply chain transparency, internal forecast methods, demand and production planning as well as setup of the DDMRP system. Hence, the purpose of this study is to investigate what is required externally from the supply chain and internally in the organization in order to use the DDMRP method for generating orders towards production and suppliers. Further, the study also aims to investigate the potential ways to incorporate forecast in sizing the DDMRP buffers.
One company that has met these challenges is AeroCo, which is currently in an implementation phase of DDMRP. Semi-structured interviews with 23 company representatives from various department, along with historical demand, production and delivery data, have been the foundation of the data collection. The qualitative data was gathered and analyzed using influences from a systematic approach presented by Gioia, Corley, and Hamilton. The quantitative data was compiled in excel and compared to find the best forecast method. Moreover, the literature review was used to obtain a better understanding of supply chain transparency, different forecast methods, overall demand and production planning, as well as the DDMRP method. Altogether, the theoretical framework combined with the empirical findings led to conclusions concerning the research questions.
Firstly, it can be concluded that DDMRP goes hand in hand with reaching full supply chain integration and the implementation of collaborative planning, forecasting, and replenishment. Secondly, it has been shown that relying only on the qualitative or quantitative forecast is not sufficient. For this reason, an integration method with both qualitative and quantitative approaches should be included. Thirdly, regarding the internal demand and product planning processes, it can be noted that the sales and operations planning process does not have to go through major changes in order to use the DDMRP method. However, the master production scheduling process will need to be further adjusted. Lastly, when incorporating the forecast into DDMRP, quality errors do not need to be incorporated since it is handled by a variability factor. Instead, the forecast used for DDMRP should reflect the general forecast but include a demand adjustment factor in order to take vacations and other capacity constraints into consideration
