Inledning: Marknadstillväxten har gått framåt senaste åren och företag bör hitta konkurrensfördelar för att fortsätta vara lönsamma. Priser bör anpassas efter marknaden och vetskap om tillverkningskostnad blir viktigt för tillverkande företag. För att beräkna tillverkningskostnad för produkter kan självkostnadskalkylering och totalkostnadsmodellen användas. Ett materialflöde i en produktion består av processer som innefattar hantering, förflyttning och lagring av material. Studien har inte funnit någon tidigare forskning eller modell som förklarar relationen mellan materialflöden och tillverkningskostnad på en detaljerad nivå vilket motiverar studien. Syfte: Syftet med arbetet var att utforma och utvärdera en modell för bestämning av tillverkningskostnad med utgångspunkt från materialflöden i produktion med avseende på lagring, transport och tillverkningsoperationer. Metoder: En abduktiv ansats har använts för att besvara syftet och frågeställningar där teori och empiri har inhämtats parallellt under arbetets gång. I studien har teori och empiri lagt grund för kostnadsfaktorer som påverkar tillverkningskostnaden. Utformning av modell för bestämning av tillverkningskostnad: I studien har teoretiska och empiriska undersökningar utförts för att redogöra för olika kostnadsfaktorer som påverkar tillverkningskostnaden. Modellen använder tre aktiviteter för att kategorisera identifierade kostnadsfaktorer i ett materialflöde: operation, lagring och transport. Tillämpning och utvärdering av modell: Modellen tillämpades på fallföretaget Alderholmens mekaniska. Efter tillämpningen utvärderades modellen där styrkor och utvecklingsmöjligheter presenterades. Slutsats: Studiens bidrag är en modell för beräkning av tillverkningskostnad med utgångspunkt från materialflödet i produktionen. Modellen presenterar vilka faktorer som påverkar tillverkningskostnaden. Kapitlet avslutas med rekommendationer till framtida studier för att utöka kunskapen inom ämnet.

Urban gondola lift systems are becoming a regular sight rather than a rarity throughout the globe. Authors attribute their increasing popularity to factors such as environmental sustainability, operational reliability and cost efficiency compared to other right-of-way transit solutions. Replacing conventional modes of transit with urban gondolas cannot however be achieved without tackling several operational challenges. As potential new operators often lack the human resources and knowledge base required to successfully man, operate and maintain systems, they turn to manufacturers for increased after-sale support. Companies of the Doppelmayr Garaventa Group, the world’s largest manufacturer of gondola lifts, responded to these demand patterns by offering complete operations & maintenance contracts which, among other services, include the delivery and installation of reserve components. Calculating the total cost of such components for the life cycle of a system however still proves to be demanding and requires new computational models to increase its efficiency. The applicative purpose of this paper was thus set to formulate a model that is capable of performing life cycle cost calculations for components of urban gondola lift systems, according to a set of criterion defined by industrial entities. Its research aim is accordingly to answer questions about how concurrent instruments are set up, what models does contemporary research regard as efficient in similar industries and whether these models are able to enhance life cycle cost calculation capability within the urban gondola lift market. These aims were achieved through an analysis of current company practices, followed by the formulation of two new model alternatives based on a review of contemporary scientific literature, and concluded by an iterative process wherein the two alternatives were compared to each other in terms of performance and then merged to combine the best performing features of each version. Through a second iteration, the merged model was then compared to current instruments and established as the superior choice, using industry criteria. The paper concludes by resolving the research questions it set out to answer and making further recommendations for the direction of future research and studies.

Traffic planners are facing a big challenge with an increasing demand for mobility and a need to drastically reduce the environmental impacts of the transportation system at the same time. The transportation system therefore needs to become more efficient, which requires a good understanding about the actual travel patterns. Data from travel surveys and traffic counts is expensive to collect and gives only limited insights on travel patterns. Cellular network data collected in the mobile operators infrastructure is a promising data source which can provide new ways of obtaining information relevant for traffic analysis. It can provide large-scale observations of travel patterns independent of the travel mode used and can be updated easier than other data sources. In order to use cellular network data for traffic analysis it needs to be filtered and processed in a way that preserves privacy of individuals and takes the low resolution of the data in space and time into account. The research of finding appropriate algorithms is ongoing and while substantial progress has been achieved, there is a still a large potential for better algorithms and ways to evaluate them. The aim of this thesis is to analyse the potential and limitations of using cellular network data for traffic analysis. In the three papers included in the thesis, contributions are made to the trip extraction, travel demand and route inference steps part of a data-driven traffic analysis processing chain. To analyse the performance of the proposed algorithms, a number of datasets from different cellular network operators are used. The results obtained using different algorithms are compared to each other as well as to other available data sources. A main finding presented in this thesis is that large-scale cellular network data can be used in particular to infer travel demand. In a study of data for the municipality of Norrköping, the results from cellular network data resemble the travel demand model currently used by the municipality, while adding more details such as time profiles which are currently not available to traffic planners. However, it is found that all later traffic analysis results from cellular network data can differ to a large extend based on the choice of algorithm used for the first steps of data filtering and trip extraction. Particular difficulties occur with the detection of short trips (less than 2km) with a possible under-representation of these trips affecting the subsequent traffic analysis.

Purpose – The purpose of the research is to explore how to reduce waste in value flows and to minimize the bullwhip effect within operations. To fulfill and answer the purpose of the research three questions of issue has been established: 1. What issues in value flows can be identified, regarding inbound and outbound flows? 2. How can issues in value flows be minimized, with regards to inbound and outbound flows? 3. How can a model be created to understand the relationship between value flow improvements and the bullwhip effect? Method – To retrieve understanding of the topic that thesis involves, support of literature studies, observations and data collection was used. The literature study created a foundation of theoretical framework. The data collected from the case company formed a base that partly facilitates the purpose of this thesis. The theoretical framework and data collection were thoroughly analyzed and discussed in order to propose solutions for improvements. Findings – The research establishes different issues that can be identified in outbound and inbound flows such as; waste in transportation, waste in inventory, waste in movement and waste in overproduction. Further, in order to minimize the identified issues in inbound and outbound flows it is imperative to find out the root cause for the issues. When the root cause was established, statistical approach was utilized to further explain the issue. The findings from the statistical approach elucidated a large variance between supply and demand, resulting in a bullwhip effect. In order to minimize the bullwhip effect, improvements should focus on insufficiencies such as; lack of communication, order batching and disorganization. In addition, standardization through 5s approach mitigates the waste in transportation and movement. To understand the relationship between value flow improvements and the bullwhip effect, a causal loop diagram was created to understand the phenomenon from a system perspective. Implications – The research contributes with solutions on how to identify the bullwhip effect as well as highlighting the issues in value flows. Furthermore, this research solidifies the importance of using lean process to improve overall productivity in value flows. Limitations – The research was limited to one case company and one area in the case company. The answers that are presented in this research could increase the reliability and credibility if the authors had been able to investigate several areas at the case company or several companies. Furthermore, the date that has been retrieved is based solely on one supplier at the case company. Keywords – ‘Lean Process’, ‘Bullwhip Effect’, ‘Supply Chain Management’, ‘Continuous Improvement’, ‘System Perspective’ and ‘Statistical Analysis’.

Introduction: In today’s global world, supply chain and logistics operations have become far too complicated to be handled by individual firms. Nowadays, it is dealt by logistics and freight solution providing companies. The companies introduce an amount of flexibility for the firms doing their business. The performance of supply chain operations depends upon various dimensions such as location, quality, on-time delivery, dependability and cost. Reducing the operational costs by increasing effectiveness of process helps to gain a competitive advantage. Background: Logistics is a highly labour intensive industry. The primary role of a distribution centre as a supply chain element is to sort and forward the incoming goods(parcels) as effectively as possible within the minimum time. Due to the varied physical attributes of incoming goods/parcels, the sorting process in distribution centres involves different handling techniques. One such technique is the use of a parcel sorter conveyor system, there are various factors based on which the output increases or decreases in such systems. Flexibility is a factor that is seldom compromised, thus failing to operate effectively when volume increases, reduce a competitive advantage for the any distribution centre. Purpose: The purpose is to identify reasons for ineffectiveness during the process and find improvement opportunities which enables a distribution centre to handle more volume on a daily basis. Case: This single case study is carried out at a regional distribution centre aiming to grow regarding the number of suppliers and volume of handled parcels. Findings: The sources of ineffectiveness and improvement opportunities were identified (some of the improvement opportunities are case specific). Discussions: The study provides evidence that errors which are thought to be caused due to human actions can have other root causes, a synergetic approach is suitable in situations where high interdependency of variables exist.   Conclusions: The study has focused on a single case study, conducting the similar type of study with other companies working within a similar environment can provide more generalisable evidence. Improvement should be seen with a mentality of sustaining, with high variability of changes occurring, there should be a focus towards continuous improvement as well.

During the last century, the number of car users has increased as an effect of the increasing population growth. To manage the environmental and infrastructural challenges that comes with a more congested traffic network, traffic planning has become of higher importance to analyze the current traffic state and to predict future capacity challenges and effects of investments. These analysis and evaluations are commonly performed in different traffic analysis tools, where updated and realistic traffic demand needs to be provided to ensure reasonable results. In this thesis, a macroscopic model of Norrköping municipality constructed in the traffic demand modelling software Visum and a daily Origin-Destination(OD)-matrix is considered. The goal of this thesis is to produce a method that modify the current daily demand matrix into hourly demand matrices, called hourly target matrices, that represents a typical weekday. The goal is also to implement and evaluate the OD-estimation algorithm Simultaneous Perturbation Stochastic Approximation (SPSA) to obtain updated and valid demand matrices for the network model of Norrköping. The method of dividing the daily demand matrix into hourly target matrices is based on the paper by Spiess %26 Suter (1990). The method makes use of the available daily trip purpose matrices combined with hourly link flow observations from 96 links in a multiple linear regression model to obtain 24 hourly demand matrices. The resulting matrices are compared with the link flow observations and has different levels of R^2-fit, the maximum fit is 85.79 % and the minimum fit is 55.89 %. The average R^2-value is 72 %. The OD-estimation based on SPSA is performed on the AM and PM peak hours. The algorithm is implemented in Python scripts that are called from Visum where the traffic assignments is calculated. The result is an increase in R^2-value since the link flow difference between estimated and observed link flow is decreased. In total, the estimated link flows are improved by 7.4 % in the AM peak hour and 15.6 % in the PM peak hour. The total absolute change in OD-demand is 3 871 trips for AM peak hour and 6 452 trips for the PM peak hour. The estimated OD-matrices are evaluated by qualitatively visualizing the difference in heat maps and in the quantitative measure structural similarity index. The result is no major structural change from the hourly target matrices which verifies that the information used when the target matrices is produced still is considered. The total demand increased in both hours, with 505 respectively 2 431 trips and flows in some OD-pairs has a very high percental change. This was restricted by adding a penalty term to the SPSA-algorithm on the PM peak hour. The result of penalized SPSA is a much less increase of total demand as well as less percental change of the OD-flows. Though, this to a cost of not decreasing the link flow difference in the same magnitude.

The use of GPS observations for investigating routing behaviors can be a good alternative to using more traditional traffic simulation models. In this paper, a method for inferring paths from GPS observations is proposed. Further, a route set generation algorithm is implemented. The inferred trips are used for the calibration of the parameters in the route set generation algorithm. The investigated network is part of the Interstate 210 freeway east of Los Angeles, USA. The results shows significant differences in number of eastbound travelers choosing to travel north of, south of, and on the freeway during regular days compared with the incident day. The travel times are also higher during the incident day. Different travel times as costs on the links have a large impact on the results from the route set generation algorithm. The conclusion is that the implemented methods can be used to gain a better understanding about routing behavior. However, to use the results for decision making, more input data with better precision should be used.

With reliable models to forecast travel demand, traffic planners and decision-makers can be assisted in choosing the best solutions to obtain traffic performance goals. Practitioners have traditionally been relying on infrequent, costly and respondent pressurized travel surveys as their main source of data for these models. The drawbacks of the data collection method highlight a need to search for alternative sources of data used for the purpose. One such source is public transport “tap-in” data. This thesis executed a case study with the target of improving the travel demand model of Norrköping via public transport data. An algorithm that estimates the alighting station of travellers was applied to a data set provided by the public transport operator of the city. By allocating the OD-demand from stations to the traffic analysis zones used in the model a straightforward integration method using the tap-in estimate as a reference matrix could be used. The target with the method was to redistribute the demand in such a way that the public transport demand approached the tap-in estimate but that the total demand for all modes for the OD-pair remained unchanged. The results gave some indication that the integration of tap-in data improved the model performance from the perspective of public transports. In a regression analysis comparing the number of entries per station the integration of tap-in data increased the correlation coefficient from 0,845 to 0,864. Further was the performance for other transport modes seemingly not worsened by the integration of tap-in data. Finding an allocation procedure that was generic but still accurate proved complex. Further were drawbacks with the integration procedure highlighted where the method executed affected the results of the model, not its behaviour. The consequence of this is that, though the model might be an accurate representation of the current state of traffic, it is difficult to execute the same procedure when investigating future states. Still, the thesis stressed some of the potential for public transport data in modelling contexts, where the role of the data, given the procedure executed, still is of complementary character to travel surveys.

Syfte – Studien syftar till att kartlägga hur kundorderpunktens position förhåller sig till företags val av säkerhetskapacitetsbuffertar för att hantera stokastiska variationer i kapacitetsbehov. Därmed är studiens frågeställningar: Vilka är de huvudsakliga säkerhetskapacitetsbuffertarna som används för att hantera stokastiska variationer i kapacitetsbehov? Hur förhåller sig kundorderpunktens position till val av säkerhetskapacitetsbuffertar för att hantera stokastiska variationer i kapacitetsbehov? Metod – För att besvara studiens frågeställningar har en fallstudie genomförts och inkluderar en litteraturstudie, intervjuer och dokumentstudier. Intervjuer genomfördes med sju respondenter från sex företag och empirin som framkom från intervjuerna och dokumentstudier analyserades tillsammans med teori från litteraturstudien för att få fram studiens resultat. Resultat – Studien har identifierat tio tillvägagångssätt för att hantera stokastiska variationer, varav två som inte tidigare nämnts av studiens teoretiska ramverk. De tio tillvägagångssätten har därefter kategoriserats in i sex säkerhetskapacitetsbuffertar baserat på likheter. Efter identifiering av kundorderpunktens position har möjliga kopplingar mellan kundorderpunktens position och val av säkerhetskapacitetsbuffert analyserats för att undersöka eventuella samband. Tre tendenser till kopplingar har identifierats men vidare studier krävs för att säkerställa kopplingarna. Implikationer – Området kring hantering av variationer i kapacitetsbehov med en uppdelning i en kapacitetsbuffert och en säkerhetskapacitetsbuffert är relativt outforskat. Att undersöka eventuella kopplingar mellan val av säkerhetskapacitetsbuffertar och kundorderpunktens position kan fylla ett kunskapsgap och kan teoretiskt bidra till vidare studier inom området säkerhetskapacitetsbuffertar. Genom att lära av andras erfarenheter ges en ökad förståelse vilket kan hjälpa företag att fatta mer välgrundade beslut vilket kan leda till förbättrad prestation, vilket är studiens praktiska bidrag. Begränsningar – Studiens begränsning ligger i att endast sju respondenter från sex företag ingick i studien, där endast en intervju gjordes med respektive respondent. Antalet använda tillvägagångssätt och deras kopplingar till kundorderpunktens position hade kunnat stärkas ifall ett större antal respondenter från olika typer av företag deltagit i studien. Därigenom hade kopplingarnas generaliserbarhet kunnat stärkas. Dessutom hade troligtvis fler tillvägagångssätt identifierats ifall en större bredd studerats. I studien har den totala kapaciteten hanteras som två separata delar för hantering av förväntade och oväntade behov. Infallsvinkeln är relativt ny och är inte etablerad vilket kan försvåra och begränsa förutsättningen för verksamheter att applicera resultatet. / Purpose – The study aims to map how the position of the order penetration point is related to companies’ choice to handle stochastic variations in capacity requirements through the use of safety capacity buffers. Hence, the research questions are: 1. Which are the main safety capacity buffers used to handle stochastic variations in capacity requirements? 2. How is the position of the order penetration point related to the choice of safety capacity buffers to handle stochastic variations? Method – A case study has been conducted in order to answer the research questions and thus includes a literature study, interviews and document studies. The interviews were conducted with seven respondents from six companies and the empirical data that emerged from the interviews and document studies were analysed together with theory from the literature study to reach the result of the study. Findings – The study has identified ten approaches to handle stochastic variations, two of which was not previously mentioned in the theoretical framework. The ten approaches have then been categorized into six safety capacity buffers based on similarities. After identifying the position of the order penetration point possible connections between the position of the order penetration point and choice of safety capacity buffers have been analysed to explore possible relationships. Three tendencies to connections have been identified but further studies are required to ensure the connections. Implications – The research area of handling variations in capacity requirements with a division in one capacity buffer and one safety capacity buffer is relatively unexplored. Exploring possible connections between the choice of safety capacity buffers and the position of the order penetration point could fill a gap of knowledge and theoretically contribute to further research within the area of safety capacity buffers. Learning of others’ experiences gives an increased understanding which can help companies to make more informed decisions that can lead to better performance, which is the practical contribution of the study. Limitations – The studies limitations lies in that only seven respondents from six companies were included in the study, were only one interview was conducted with each respondent. The number of used approaches and their connections to the order penetrations point could have been strengthened in case an increased number of respondents from different kind of companies had participated in the study. Thereby the connections’ generalizability could have been strengthened. Additionally more approaches probably would have been identified in case a greater width had been studied. In the study the total capacity have been handled as two separated parts to handle expected and unexpected requirements. The approach is relatively new and not established which can complicate and limit the ability for companies to apply the results.

The purpose with the study is to provide a basis for an implementable, improved returns management process. This will help to obtain an empirical result for Lager 157 and to fill any scientific knowledge gap. The study has been divided into two research questions that are of a hierarchical nature. The authors first want to map the return process in order to then make suggestions for improvements using collected data along with collected theory. Method – A single case study has been conducted because the authors are studying a process and want a more in-depth knowledge. The study is carried out on Lager 157, who is active in fashion retailing and has a pronounced strategy for omnichannels, where they use both stores and e-commerce. Because the study only is made on one company, the external validity will be low. But the authors will compare collected theory with the empirics, which will increase the external validity. The literature has been collected through different sources, such as; databases, snowballing and recommendations from teachers and fellow students. The methods for collecting data has been; interviews, observations and document studies. Triangulation of data has ensured that the collected data is correct. Findings – The authors have, together with data and theory, provided a basis on how the study company could improve their returns management. The basis stated is that a web-based return registration should be implemented early in the process but also that the stores should use the same ERP as they do in the e-commerce department. These suggestions are based on that the study company should highlight activities such as gatekeeping and return avoidance, which leads to an improved returns management. Because of these changes, the company can increase their process speed but also improve their process integration and take a step towards fully integrated omni channels. Implications –The study has provided with both empirical and scientific implications. The study company has, from the results, got an overview of their returns management but also been provided with suggestions that can lead to an improved returns management in the future. In the results, the study company can also see which effects these suggestions could have and see how the new returns management could look like compared to have it looked before. During the literature study, the authors found that research connected to omni channels and the focused area were missing. Based on this the authors have created a model which illustrates what the companies should prioritize. Because the study only is made on one single company, the authors thinks that there is room for further research where the model could be evaluated and evolved to fit a greater number of companies. Limitations – Because of a time limit of the study, a single case study was considered to be of high relevance. It gave the authors the opportunity to use different methods to collect data in order to strengthen the results obtained. The external validity would have been higher if an multi case study would have been conducted with a quantitative approach. The interviews where following a semi-structured structure because the authors wanted to gather a large amount of information and leave space for follow-up questions. The observations were unstructured in order to make sure that the observation object where acting naturally. On the other hand, a structured observation would have shown differences and deviations in the activities. The document studies were only used to find out which type of data that the study company did collect. This could have been more extensive in a quantitative focus on the study. / Syfte – Syftet med studien är att ta fram underlag för en implementerbar, förbättrad returprocess. Detta skall bidra till att få fram ett empiriskt resultat åt Lager 157 samt att fylla igen eventuella vetenskapliga kunskapsgap. Studien har delats in i två forskningsfrågor av en hierarkisk karaktär. Författarna vill först kartlägga returprocessen för att i sedan ta fram underlag för förbättringar med hjälp av insamlade data tillsammans med insamlad teori. Metod – En enfallsstudie har genomförts då författarna ämnar studera en process och vill ha en mer djupgående kunskap. Studien är genomförd på Lager 157 som är verksamma inom mode och har en uttalad strategi för omnihandel, där de använder sig av både butiker och e-handel. Då studien enbart är genomförd på ett fallföretag så kommer den externa validiteten vara låg. Däremot ämnar författarna jämföra insamlad teori med empirin, vilket stärker den externa validiteten. Författarna har samlat in litteratur genom olika tillvägagångssätt, såsom; databassökningar, snöbollsmetoden samt rekommendationer ifrån handledare och medstudenter. De metoder som har använts för att samla in data är; intervjuer, observationer och dokumentstudier. Triangulering av data har säkerställt att den insamlade data är korrekt. Resultat – Tillsammans med insamlade data och teori har författarna tagit fram underlag för hur fallföretaget skulle kunna förbättra sin process. Det underlag som tagits fram är dels att en webbaserad returregistrering bör implementeras tidigt i flödet samt att butikerna och e- handeln bör använda sig av samma affärssystem. Detta underlag har sin grund i att fallföretaget bör lyfta fram aktiviteter så som gatekeeping och return avoidance, vilket leder till en förbättrad returprocess. Effekterna anses bidra till att fallföretaget kan öka sin bearbetningshastighet men också förhöja sin processintegration och ta ett steg mot en fullt integrerad omnihandel. Implikationer – Studien har både tagit fram empiriska och vetenskapliga implikationer. Dels har fallföretaget utifrån studiens resultat fått en överblick i hur returprocessen ser ut men också fått ett underlag med åtgärdsförslag som kan leda till en förbättrad returprocess i framtiden. I studiens resultat kan fallföretaget se vilka effekter detta kan mynna ut i men också hur det nya flödet skulle komma att se ut i de båda kanalerna. Då forskning inom omnihandel kopplat till det studerade området ansågs saknas så har författarna tagit fram en modell som illustrerar vad företag bör prioritera. På grund av att studien enbart är genomförd på ett företag anser forskarna att det finns ett tillfälle för vidare forskning, där modellen kan utvärderas och utvecklas för att passa ett större antal företag. Begränsningar – Då författarna har en tidsbegränsning kopplat till arbetet ansåg författarna att en enfallstudie var av högst relevans. Detta gav även möjligheten för författarna att ta användning av olika datainsamlingstekniker för att stärka de resultat som tagits fram. Om en flerfallstudie hade genomförts med mer kvantitativ datainsamling hade det gett en mer överblickande bild, vilket skulle kunna stärka den externa validiteten. De intervjuer som genomfördes följde en semistrukturerad struktur då författarna ämnade att samla in en stor mängd information och där utrymme fanns för följdfrågor. De observationer som genomfördes var ostrukturerade för att säkerställa att observationsobjekten betedde sig naturligt. Däremot hade en strukturerad observation visat på skillnader och avvikelser i aktiviteterna. Dokumentstudierna användes enbart för att säkerställa vilken typ av data som samlades in i dagsläget och kunde ha varit mer omfattande vid en kvantitativ inriktning på studien.