Background With large amounts of polyvinyl chloride (PVC) in the waste streams, recycling of PVC and more sustainable processes have become increasingly important. The sustainable development of processes has received a lot of attention in the last decades because of the increasing environmental threat. It is also important to be efficient in order to stay competitive in the market. Traditional methods for improving efficiency like lean disregards the sustainable aspect. Green methods focus on environmental impact and omit efficiency. The concept of lean and green enables and ensures the integration of efficiency and sustainability. Firms need to improve their efficiency without sacrificing sustainability and environmental impact as a consequence of becoming more competitive. Therefore, there is a great need of support for decision-making regarding efficiency and sustainability. Objectives The objective of this thesis is to provide support for decision-making in recycling environments where the focus is to improve efficiency and sustainability performances simultaneously. This thesis aims to increase the knowledge regarding integration of efficiency and sustainability as support for decision-making. Methodology A model based on the concept of lean and green was developed with commonly used indicators to evaluate efficiency and sustainability. To examine the applicability of the model, a case study was conducted at a company on a PVC recycling process. Data was collected at the company to create different scenarios based on lean and green practices, which were analyzed using discrete event simulation. These scenarios were then evaluated through the model in order to improve efficiency and sustainability. Results The result showed a reduction in lead time of 55.99%. An increase in throughput and carbon dioxide savings of 30 970.85% respectively were depict due to the upscaling. An increase of 2 252.92% in total cost is needed for investment. An increase in water consumption of 7 584.89% and energy consumption of 1 733.71% was denoted as a consequence of the upscaling. Trade-offs between and within efficiency and sustainability were reviled. Conclusions The study presented a model which can be used as support for decision-making for recycling processes which integrates efficiency and sustainability. Efficiency and sustainability are integrated through the application of the concept lean and green. The model supports decision-making by clearly visualize and compare effects, trade-offs and consequences through several key performance indicators evaluating efficiency and sustainability on a PVC recycling process based on lean and green implementations. By comparing the different key performance indicators, the business can improve their performance. / Bakgrund Med stora mängder avfall bestående av polyvinylklorid (PVC) har återvinning av PVC och hållbara processer blivit allt mer viktiga. Hållbar processutveckling har fått ökad uppmärksamhet det senaste decenniet på grund av ett ökande miljöhot. Samtidigt är det lika viktigt att vara effektiv för att bibehålla konkurrensfördelar på marknaden. Traditionella metoder för att förbättra effektivitet som lean utesluter hållbarhets aspekter. Green metoder fokuserar på miljöpåverkan och bortser från effektivitet. Konceptet av lean och green möjliggör och försäkrar integrationen av effektivitet och hållbarhet. Företag måste förbättra sin effektivitet utan att uppoffra hållbarhet och miljöpåverkan som en konsekvens för att bli mer konkurrenskraftiga. Därför finns det ett stort behov av underlag för beslutsfattning som behandlar både effektivitet och hållbarhet. Syfte Syftet med studien är att tillhandahålla underlag för beslutsfattning inom återvinningsmiljöer med fokus på att förbättra effektivitet- och hållbarhetsprestationer simultant. Målet med studien är att öka kunskap om integrationen mellan effektivitet och hållbarhet som underlag för beslutsfattning. Metod En modell baserad på konceptet lean och green utvecklades genom användning av vanligt förekommande indikatorer för att utvärdera effektivitet och hållbarhet. För att undersöka applicerbarhet av modellen genomfördes en fallstudie på ett företag med en PVC återvinningsprocess. Data samlades in på ett företag för att skapa olika scenarion baserade på lean och greentillämpningar, vilka analyserades genom användning av diskret eventsimulering. Scenariona blev sedan utvärderade genom modellen för att se förbättringar av effektivitet och hållbarhet. Resultat Resultatet från fallstudien visar en minskning i ledtid på 55.99%. En ökning i genomströmning och koldioxid besparingar på 30 970.85% respektive påvisades på grund av upp skalningen. En ökning på 2 252.92% i total kostnad krävs för investering. En ökning i vattenkonsumtion på 7 584.89% och i energikonsumtion på 1 733.71% erhölls som en konsekvens av upp skalningen. Kompromisser både inom och mellan effektivitet och hållbarhet uppstod. Slutsatser Studien presenterar en modell som kan användas som underlag för beslutsfattning inom återvinningsprocesser vilken integrerar effektivitet och hållbarhet. Effektivitet och hållbarhet är integrerade genom applicering av konceptet lean och green. Modellen stödjer beslutsfattning genom att tydligt visualisera och jämföra effekter, kompromisser och konsekvenser genom flertalet nyckeltal som utvärderar effektivitet och hållbarhet av en PVC återvinningsprocess baserat på lean- och greenimplementeringar. Genom jämförelse av olika nyckeltal kan företag förbättra sin prestation.

No description available.

Purpose: The purpose of the research is to explore how to use and implement acombination of the tools value stream mapping and discrete event simulation, to supportthe decision-making in the improvement process in an organization. The researchfurther takes the sustainability aspect into consideration. Method: A deductive approach is applied in order to explore and elaborate on existingtheories to fill the identified gap in the research field. To identify already existingtheories a literature review along with a systematic literature review were conducted.Further, to enable the exploration of the purpose, a case study was performed toelaborate on the industrial implementation of the combinational tool use. Findings: The studied research field is well researched but has an identified gapregarding the combinational tool use and its industrial application. Even though, theadvantages and challenges of the integration of the tools are well elaborated on inexisting research, the methodology on how to use and implement them in anorganization was identified as inadequate and therefore this research proposes such acontribution. One of the main conclusions of the study is that integrating DES withVSM early in the process is greatly advantageous in order to utilize theircomplementary capabilities and thus achieve more decisive facts right from the start,from the so-called current state. Implications: The conclusions of the conducted research showed that there are severaladvantages with the combinational tool use but also some challenges that need to betaken into account. In order to bridge these challenges and to take them intoconsideration when implementing the tool combination, an approach was developed tosupport the decision-making within the improvement process. In this study, to enabletool integration on complex production systems, aggregation modeling was applied togenerate a reliable replica of the system. Limitations: This study contains some limitations, whereas the most influentiallimitation is related to the data collection, both in regard to time constraints and validity.Due to the limited time that the researchers had at the factory site, the data collectionperiod was limited to less than 3 months. This in turn resulted in the use of smallersample sizes. The data collected from the case company have been generalized whencreating the models, this was due to the data being too complex to fully compile andunderstand, and a “good enough” perspective was then applied. This perspective is notconsidered to affect the validity or reliability of the study in the wider sense.

Emergency Departments (ED) in the US are in crisis. In 2004 between 40 and 50% of the US hospitals experienced crowding. Crowding negatively affects the quality and access of emergency care. Optimally managing the present resources in EDs and finding ways to reduce patient length of stay is critical to improving patient care in EDs. We use computer simulation modeling of patient flow in an ED (i.e. discrete event simulation) to study the impact of 1) resource management and profit optimization, 2) process changes, and 3) task prioritization on patient length of stay. Our model of patient flow, ED with multiple Acuities (EDWA), consists of a five-fold process of emergency care which represents five different types of patients. This model assigns each patient to an individual doctor and allows patient treatment process to proceed simultaneously or sequentially with other activities. The results show an increase in the need for resources with an increase in variability; the dependency of the optimal resource mix on the objective we want to optimize; and the relationship between quality of emergency care and profitability. Further, our findings imply that bedside registration (a commonly recommended process change in EDs) should only be implemented when emergency department beds are free.

No description available.

This thesis presents the work of a master degree project in mechatronics by two students from The Royal Institute of Technology. The project was carried out during spring 2017 in collaboration with Bosch Rexroth Mellansel as part of their desire to improve their operations. It is also in line with the Bosch Groups ambition to lead the development within Industry 4.0. The aim was to investigate the information need on a discrete manufacturing process and how radio-frequency identification (RFID) can be used to cover that need. The background research was made with qualitative methods using a literature review on relevant areas and a case study of Bosch Rexroth Mellansel. A discrete event simulation was created to confirm the possibilities of an RFID tracking system. It acted as a target for what the developed demonstrator should fulfil and was realised through a system of four wireless nodes connected in a mesh network. The plant in Mellansel partially implemented a Bosch standardised RFID system in parallel with the development of the demonstrator, which enabled a comparison of the two systems. The results show that from a tag event, which gives information on what, where and when, it is possible to, in real time, analyse and visualise valuable key performance indicators for a production process. It is also possible to use the data to automate transactions in an enterprise resource system which removes non-value adding activities from an operator while also ensuring consistency in the reporting procedure. The results indicate that benefits can be achieved. However, this requires further quantitative analysis before it can be fully confirmed and be used to push the development of Industry 4.0 forward. / Denna rapport presenterar ett examensarbete inom mekatronik av två studenter från Kungliga Tekniska Högskolan. Projektet genomfördes under våren 2017 i samarbete med Bosch Rexroth Mellansel som en del av deras strävan att förbättra sin verksamhet. Det ligger också i linje med Bosch koncernens ambition att leda utvecklingen inom Industri 4.0. Syftet var att undersöka informationsbehovet hos en diskret tillverkningsprocess och hur radio-frequency identification (RFID) kan användas för att täcka detta behov. Bakgrundsstudien gjordes med kvalitativa metoder som litteraturstudie inom relevanta områden och en fallstudie av en produktionsprocess inom Bosch Rexroth Mellansel. En simulering av produktionsprocessen skapades för att bekräfta möjligheterna av att använda ett RFID system för spårning av objekt. Den fungerade som ett mål för vad den utvecklade demonstratorn skulle uppfylla och realiserades genom en prototyp bestående av fyra trådlösa noder samlade i ett mesh nätverk. Parallellt med utvecklingen av demonstratorn gemomförde fabriken i Mellansel en del-implementering av en Bosch-standardiserad RFID lösning, vilket möjliggjorde en jämförelse av de två systemen. Resultaten visar att det från en avläsning av en tag, som ger information om vad, var och när, så är möjligt att i realtid analysera och visualisera värdefulla nyckeltal för en produktionsprocess. Det är också möjligt att använda data för att automatisera transaktioner i ett affärssystem som tar bort icke värdeskapande aktiviteter för operatören och samtidigt säkerställer en standardiserad rapporteringsprocess. Resultaten visar att fördelar kan uppnås men kräver ytterligare kvantitativ analys innan de kan bekräftas till fullo och användas för att driva utvecklingen av Industri 4.0 framåt.

This master’s thesis explores the application of Modeling and Simulation (M&S) techniques in military operations involving Forward Arming and Refueling Points (FARP). FARPs play a crucial role in supporting aircraft operations by facilitating deep penetration into enemy territory and ensuring sustained presence in the Area of Operation (AOO). Due to the limited reach of aircraft, FARPs often become essential for accessing the AOO. Logistical units that are responsible for establishing FARPs, face the challenge of timely deployment, as joint air operations planning is complex and time-consuming. M&S is employed to enhance the efficiency of FARP planning processes for military helicopters.M&S allows for the testing of various solutions without the need for physical experiments, thereby enabling the exploration of different options during the planning phase of FARP operations. The Information Systems (IS) framework is utilized to create a theoretical knowledge base, forming the foundation for developing a M&S product tailored to the requirements of FARP operations.This master’s thesis utilizes the Fuzzy Cognitive Mapping (FCM) method to construct a model of FARP operations, while employing Monte Carlo Simulation to quantify associated risks and discrete event simulation to simulate the time aspects of such operations. The outcomes include a Python-based simulation program that interprets real-world map images, simulates FARP operations, and generates data such as helicopter fuel consumption and FARP survival probability.Although the simulation program has limited functionality, it demonstrates the potential of M&S to support decision-making processes for FARP commanders, which can enhance the overall efficiency of the FARP planning process. This is shown by a Spearman correlation test and Student's t-test, which revealed significant relationships among different elements of the model, reflecting the dynamics observed in real- world FARP operations. Further enhancements can be made to the simulation program by incorporating additional dynamic elements of the model.

No description available.

[pt] Nesta tese, abordamos o escalonamento de profissionais de saúde para propor um uso mais eficiente da capacidade existente e fornecer acesso oportuno em diferentes serviços de saúde. Apresentamos um conjunto de problemas relacionados à programação de equipes de saúde. O primeiro problema procura reduzir o tempo de porta-médico em uma unidade de pronto atendimento; o segundo problema visa reduzir o tempo de espera total de tratamento também em uma unidade de pronto atendimento; o terceiro problema visa fornecer acesso oportuno à consulta clínica e à cirurgia em uma unidade cirúrgica especializada. Foram propostos e resolvidos modelos de programação estocástica de dois estágios que procuram representar com precisão as características particulares inerentes a cada problema. Um aspecto importante em problemas de saúde é o grande número de incertezas envolvidas nos processos. A incorporação da incerteza aumenta a complexidade do problema e, portanto, torna-se impossível computacionalmente considerar todos os cenários possíveis. Essa dificuldade é contornada usando a Aproximação por Média Amostral (SAA) para representar a incerteza na demanda. Modelo de simulação de eventos discretos (DES) é usado para representar os problemas. Por fim, as soluções foram aplicadas a estudos de caso reais, mostrando que os modelos propostos são adaptáveis a diferentes prestadores de serviços de saúde. Ao longo da tese, resolvemos com eficiência os modelos utilizando casos reais de hospitais no Brasil e nos EUA. / [en] In this thesis, we approach the problem of healthcare staff scheduling to propose a more efficient use of existing capacity to provide timely access in different health services. We present a set of problems related to healthcare staff scheduling. The first problem seeks to reduce the door-to-doctor time in an Emergency Department; the second problem aims to reduce the waiting time of the overall treatment also in an Emergency Department; the third problem aims to provide timely access to both clinic and surgery in a specialized surgical unit. We formulate and solve two-stage stochastic programming models that seek to accurately represent the particular features that are inherent of each problem. An important aspect in healthcare problems is a large number of uncertainties involved in the processes. The incorporation of the uncertainty increases the complexity of the problem, and it, therefore, becomes computationally infeasible to consider all of the possible scenarios. We circumvent this difficulty by relying on Sample Average Approximation (SAA) to address the demand uncertainty. We also use a discrete-event simulation (DES) model to represent the problems. Finally, we apply the framework to real case studies showing that the proposed models are adaptable to different healthcare providers. Throughout the thesis, we efficiently solve the models using real cases of Brazil and USA hospitals.

In order for the companies to be competitive in today’s market, it is vital to adapt quickly to the market trends. The steady shift towards mass customization from mass production has been challenging many industries globally, which demands the use of digital tools and technologies in various areas to improve performance throughout the supply chain processes. One of these areas is short-term scheduling of jobs on the shop floor. Short-term scheduling of jobs plays a very vital role in many production systems. Optimisation of short-term scheduling help the companies in improving their operational Key Performance Indicators (KPIs), thus saving both money and resources. Today’s complex production systems with multiple constraints, system level interactions and the dynamic environment have challenged the traditional static scheduling approaches. These complex production systems require new scheduling approaches which can consider all the dynamics and should be capable of real-time reconfiguring in case of uncertainties in the shop floor. In this thesis, a case study was performed in a steel manufacturing company over the period of five months to validate Discrete Event Simulation (DES) as a tool for short-term scheduling of heavy plates in a dynamic environment. The challenges related to DES for short-term scheduling during model design, development and implement phases were also identified. In addition to this, the requirements to implement DES model for short-term scheduling in a dynamic environment were also discussed. Furthermore, a Systematic Literature Review (SLR) was also conducted to support the empirical findings from the case study. The idea of this study was to generate an optimal schedule by minimizing overall makespan and maximizing resource utilization using DES model. The findings from both SLR and DES model has clearly proven that DES as a digital tool is exceptional for short-term scheduling in a dynamic environment, nevertheless there are still some challenges associated which needs to be investigated further. The same model can also be used for other purposes such as analysing and identifying bottlenecks in the whole production system. / För att företagen ska vara konkurrenskraftiga på dagens marknad är det viktigt att snabbt anpassa sig till marknadstrenderna. Vägen mot mass-anpassning från massproduktion har utmanat många industrier globalt, vilket kräver användning av digitala verktyg och tekniker inom olika områden för att förbättra prestandan under hela leveranskedjans processer. Ett av dessa områden är kortsiktig schemaläggning av arbeten på fabriksgolvet. Kortsiktig schemaläggning av arbeten spelar en mycket viktig roll i många produktionssystem. Optimering av kortsiktig schemaläggning hjälper företagen att förbättra sina operativa nyckeltal, vilket sparar både pengar och resurser. Dagens komplexa produktionssystem med flera begränsningar, systemnivåinteraktioner och den dynamiska miljön har utmanat de traditionella statiska schemaläggningsmetoderna. Dessa komplexa produktionssystem kräver nya schemaläggningsmetoder som kan ta hänsyn till all dynamik och bör ha möjligheten att omkonfigurera i realtid vid osäkerheter på fabriksgolvet. I denna avhandling genomfördes en fallstudie i ett ståltillverkningsföretag under fem månader för att validera Diskret händelsestyrd simulering som verktyg för kortsiktig schemaläggning av grovplåtstillverkning i en dynamisk miljö. Utmaningarna relaterade till Diskret händelsestyrd simulering för kortsiktig schemaläggning under modellens design, utveckling och implementeringsfaser identifierades också. Utöver detta diskuteras också kraven för att implementera Diskret händelsestyrd simulering för kortsiktig schemaläggning i en dynamisk miljö. Dessutom genomfördes en systematisk litteraturstudie för att stödja de empiriska resultaten från fallstudien. Tanken med den här studien var att generera ett optimalt schema genom att minimera den totala schemalängden och maximera resursutnyttjandet med hjälp av Diskret händelsestyrd simuleringsmodellen. Resultaten från både den systematiska litteraturöversynen och Diskreta händelse simuleringsmodellen har tydligt bevisat att Diskret händelse simulering som ett digitalt verktyg är exceptionellt för kortsiktig schemaläggning i en dynamisk miljö även om det fortfarande finns några utmaningar som måste undersökas ytterligare. Samma modell kan också användas för andra ändamål som att analysera och identifiera flaskhalsar i hela produktionssystemet.