Thèses : « Complex Material Handling Systems »

1

Del, Grosso Domenico. « Simulation-Based Control of Complex Material Handling Systems ». Doctoral thesis, Universita degli studi di Salerno, 2010. http://hdl.handle.net/10556/116.

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2008-2009
Material Handling (MH) consists in the movement and storage of parts, in a manufacturing or distribution process, from one location to another. Material Handling Systems (MHSs) are everywhere in production plants, assembly lines, product distribution, logistics, intermodal activities (railways, road transportation, container ships, etc..). They usually are distributed, sometimes itinerant and often mixed manned and automated. Although not adding value in the manufacturing process, MH usually influences great part of a company’s operation costs, especially, for example, in the food distribution chain. Due to the increasing demand for a high variety of products, flexibility and efficiency are two important keywords in MHSs. Optimizing MH activities means having shorter response times and an increased throughput of the plant. The importance of this optimization process is very high in today’s companies. Nowadays, the interest in this process is growing rapidly since several new technologies, like the Radio Frequency Identification (RFID) are available which finally allow to introduce an automation level to operating MHSs, almost without stopping operations and at a very low cost. In MHSs control iusses involve the problem of the optimal sequencing and scheduling of short-term activities. The so-called problem of "Dispatching” consists in defining a procedure to assign resources to missions. This is often made by using heuristic rules called Dispaching rules. For control purposes, a model of the system is necessary. Due to the complex and heterogeneous nature of MHSs, modeling approaches proposed in the literature are typically very specific and context-dependent. Moreover, the strong combinatorial nature of the control problem, and the presence of a great number of constraints to be considered, usually make the design of a control solution very tough. To devise a closed form analytical control action can require a great computational effort and could result not so convenient. Indeed, turbulence and variations in the input set of the system can suddenly make not more adequate a hardly designed control action. Thus, the choice of Dispatching rules as control actions, despite producing only local optimum solutions, is very usual for MHSs. Dispatching rules, indeed, result in a more reasonable and robust way to control MHSs since they are effective and computationally inexpensive. In the absence of a closed form control solution, Simulation is fundamental to evaluate the effects of a control action which cannot be analytically predicted. The outcome of the application of a rule or another can be easily tested via simulation and this is the reason why having a good model assumes a further major importance. In this thesis a unique arcchitecture for the modeling and the control of complex MHSs has been proposed.
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Zhao, Ying. « Optimization of cooperative material handling systems ». Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37837710.

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Zhao, Ying, et 趙穎. « Optimization of cooperative material handling systems ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37837710.

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Woo, Siu-on. « Dynamic routing for automated material handling systems ». Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B35679207.

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Woo, Siu-on, et 胡兆安. « Dynamic routing for automated material handling systems ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B35679207.

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6

Henriksson, Johannes. « Support systems for material handling in forklifts ». Thesis, KTH, Ergonomi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-145878.

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The world is becoming more and more globalized. The transportation and trading of goods across borders are becoming more frequent. All this is putting greater demands on companies dealing with material handling and distribution of supply. Material handling with forklifts is an area which is associated with risk of accidents. Statistics from both the US and Europe shows that damages to material and personnel is frequent. A certain area that is in need of improvement is the handling of material on high storages. These storages can be as high as 15m. When stacking and picking pallets at those heights it is very hard for the driver to get a good view of the pallet and handle the material in a safe way. There are several support systems available on the market today, to aid drivers with handling material on these heights. The question to be answered in this thesis is, how good are these systems and what systems should be recommended to users of forklifts? By the use of a literature study, where both available products on the forklift market as well as support systems from other markets were studied I got a good overview of available technologies. Using this information and methods for product design a number of technical concepts was generated. The concepts were limited to technologies that are available today. Because of that some technologies and concepts were overlooked. Most of the concepts consisted of a camera and a display used in different ways. A first evaluation of the concepts was made. Four concepts were chosen to be further evaluated. These four concepts were: Camera with guide lines Camera without guide lines Fork tip camera with guide lines No Camera. (benchmark) The concepts were then evaluated, tested and graded using the five criteria: Time (productivity), Safety, physical ergonomics, Usability and Preferred concept. The results showed that the concept consisting of the by TMHE used fork camera (2 above) combined with a new display and guide lines was the best support system. The result is fairly reliable because of the many different evaluation techniques used and the fact they all point the same concept. The validity however should be investigated further during a more extensive field test.

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Rocha, André Dionísio Bettencourt da Silva. « An agent based architecture for material handling systems ». Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10504.

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Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores
In the recent past, market requirements and consequently the production lines changed too. With the customization of products and the growing number of products to produce, the dy-namism and flexibility of the lines are now requirements of extreme importance. A traditional approach indicates great difficulty in satisfying those needs and as such has appeared some proposals in order to solve them. The proposed approaches are mostly related to scheduling and production planning. The transportation system is not usually inserted in the control architecture and system reconfiguration, constantly being put aside in order to this issue. This work proposes architecture to support self-organized transportation system, where it performs control functions and management. The architecture was developed for a system com-prising conveyors where the stations operate. The proposed work is a multi-agent architecture that use Dijkstra’s algorithm to improve the routing of products and materials. The main features of architecture are load balancing pre-sent in conveyors and ability to plug and unplug stations in runtime. The architecture was first tested in a virtual environment in order to check the behavior of the same and was subsequently tested in a real industrial cell in order to demonstrate its use in a real system.

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Silva, Rinaldo J. « Information processing in designing manufacturing systems with material handling ». Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/25110.

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Bartlett, Kelly K. « Congestion-aware dynamic routing in automated material handling systems ». Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53013.

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In semiconductor manufacturing, automated material handling systems (AMHSs) transport wafers through a complex re-entrant manufacturing process. In some systems, Overhead Hoist Transport (OHT) vehicles move throughout the facility on a ceiling-mounted track system, delivering wafers to machines and storage locations. To improve efficiency in such systems, this thesis proposes an adaptive dynamic routing approach that allows the system to self-regulate, reducing steady-state travel times by 4-6% and avoiding excessive congestion and deadlock. Our approach allows vehicles to be rerouted while in progress in response to changes in the location and severity of congestion as measured by edge traversal time estimates updated via exponential smoothing. Our proposed method is efficient enough to be used in a large system where several routing decisions are made each second. We also consider how the effectiveness of a AMHS layout differs between static and dynamic routing. We demonstrate that dynamic routing significantly reduces sensitivity to shortcut placement and allows an eight-fold increase in the number of shortcuts along the center loop. This reduces travel times by an additional 24%. To demonstrate the effectiveness of our proposed routing approach, we use a high-fidelity simulation of vehicle movement. To test the impact of routing methods on layout effectiveness, we developed an associated Excel-based automated layout generation tool that allows the efficient generation of thousands of candidate layouts. The user selects from among a set of modular templates to create a design and all simulation files are generated with the click of a button.

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Babiceanu, Radu Florin. « Holonic-based control system for automated material handling systems ». Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/28326.

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In real-word manufacturing environments, finding the right job sequences and their associated schedules when resource, precedence, and timing constraints are imposed is a difficult task. For most practical problems classical scheduling easily leads to an exponential growth in the number of possible schedules. Moreover, a decision time period of hours or even minutes is too long. Good solutions are often needed in real-time. The problem becomes even more complicated if changes, such as new orders or resource breakdowns, occur within the manufacturing system. One approach to overcome the challenges of solving classical scheduling problems is the use of distributed schemes such as agent or holonic-based control architectures. This dissertation presents an innovative control architecture that uses the holonic concept, capable of delivering good solutions when applied in dynamic environments. The general holonic control framework presented in this research has specific characteristics not found in others reported so far. Using a modular approach it takes into account all the categories of hardware and software resources of a manufacturing system. Due to its modularity, the holonic control framework can be used for assigning and scheduling different task types, separately or simultaneously. Thus, it can be used not only for assigning and scheduling transport tasks, but also for finding feasible solutions to the job assignment and scheduling of processing tasks, or to better utilize the auxiliary equipment and devices in a manufacturing system. In the holonic system, under real-time constraints, a feasible schedule for the material handling resources emerges from the combination of individual holon's schedules. Internal evaluation algorithms and coordination mechanisms between the entities in the architecture form the basis for the resultant schedules. The experimental results obtained show a percentage difference between the makespan values obtained using the holonic scheduling approach and the optimal values of under seven percent. Since current control systems in use in industry lack the ability to adapt to dynamic manufacturing environments, the holonic architecture designed and the tests performed in this research could be a part in the effort to build the foundations for the control systems of the next generation manufacturing systems.
Ph. D.

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Riel, Philippe F. « An evaluation process for material handling systems within FMS ». Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54401.

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The problem of evaluating new manufacturing technologies, in particular, flexible manufacturing systems (FMS) is a complex one, as its interdisciplinary nature involves multiple variables. These variables are qualitative as well as quantitative, strategic, as well as technological, intangible as well as tangible. This dissertation deals with the problem of the overall evaluation process, in particular, the evaluation of material handling systems within FMS. In particular, automated guided vehicle systems (MVS) are studied from a technical viewpoint, as they are related to strategic and economic considerations. Two main evaluation frameworks are developed. One integrates multiattribute decision models, namely, the analytic hierarchy process or AHP and the displaced ideal model (DIM), and the other integrates analytical techniques with simulation modeling. As a by product, flexibility indices are also developed for MVS and linked to the fundamental aspects of the evaluation of new technologies. This research also shows how analytical techniques can be combined with simulation modeling to form a more extensive evaluation process that includes opportunity costs as well as the usual tangible costs. Finally, a technical analysis of FMS/MVS is done on some typical cell configurations using the flexibility indices developed in this research.
Ph. D.

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Fang, Tao. « The integration of line loading and material handling ». Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/30709.

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Mullen, T. D. « Material flow control in complex manufacturing systems ». Thesis, University of Strathclyde, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360792.

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Shrivastava, Ameya R. « Simulation Modeling of Warehouse Environment Utilizing AGVS Material Handling Systems ». University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1114798132.

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Comer, Pamela Renita. « Simulation modeling of material handling systems : requirements and comparative analysis / ». Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-11102009-020221/.

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Gong, Dah-Chuan. « A metalmodel of asynchronous material transport ». Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/32868.

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Liu, Fuh-hwa Franklin. « Analytical approaches for designing a class of material flow systems ». Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/24254.

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Seibold, Zäzilia [Verfasser]. « Logical Time for Decentralized Control of Material Handling Systems / Zäzilia Seibold ». Karlsruhe : KIT Scientific Publishing, 2016. http://www.ksp.kit.edu.

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Cheung, Wing Sze. « A study of material handling system for apparel industry / ». View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?IEEM%202005%20CHEUNG.

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Chen, Ming-Te Mark. « Flow path design of a class of material handling systems for robustness and reliability ». Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/25381.

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Bakkalbasi, Omer. « Flow path network design and layout configuration for material delivery systems ». Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/25617.

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Haraldsson, Andreas, et Henrik Nederman. « Riktlinjer för utformande av informationssäkerhetspolicy : En fallstudie vid Linde Material Handling ». Thesis, Örebro University, Swedish Business School at Örebro University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-2184.

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Denna uppsats dokumenterar en fallstudie som gjordes hösten 2006 vid Linde Material Handling i Örebro. Företaget var på väg att expandera och planerade att utöka användningen av IT i verksamheten. I samband med detta gavs undertecknade i uppdrag att utforma en informationssäkerhetspolicy för verksamheten. I en litteraturstudie kunde det konstateras att det inte fanns några enklare riktlinjer för att utforma sådana policies, varmed syftet blev att göra detta. Genom en fallstudie på företaget där vi utformade en IS-policy för deras verksamhet, och även gjorde intervjuer med ledning och dokumentationsanalyser, utrönas vilka problem som kan uppstå och vilka överväganden som bör göras för att utforma en lyckad policy. Riktlinjerna kan användas av företag som känner igen sig i fallbeskrivningen. Vi har i arbetet avgränsat oss från att studera hur en policy ska införas eller utvärderas.

De riktlinjer vi utformade kan sammanfattas som följande:

* Utforma minimalistiskt

Policyn bör vara enkel, de föreskrifter och sidor som finns bör vara få till antalet och endast omfatta det absolut viktigaste.

* Tillgodose användaracceptans

Policyns innehåll ska inte uppfattas som kränkande eller alltför omständligt av de anställda.

* Formulera och ordna mål

Det är viktigt att se till att de säkerhetsmål som finns i verksamheten hjälper till att uppfylla de mer generella organisatoriska målen.

* Förankra i beslutande organ

Säkerhetsarbetet bör vara förankrat i ledningen.

* Uppdelning i delpolicies

Det kan vara aktuellt med olika delpolicies för olika delar av verksamheten

om dessa skiljer sig märkbart åt.

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Johansson, Erik. « Finding and reducing obstacles for implementing new logistics systems in the construction industry ». Thesis, Karlstads universitet, Avdelningen för företagsekonomi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-28371.

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The inefficient logistics in the construction industry is wasting vast amounts of time and resources. The major contracting firms are aware of the problem and have developed new logistics systems to reduce the waste, but all in vain. The developments are not accepted in practice. This thesis seeks to find and then reduce the factors that make implementation difficult. A literature review provides a theoretical framework. Both a quantitative and a qualitative study are addressed to site managers in larger contracting firms, as well as their suppliers. Results reveal that the three major obstacles are organisational inertia, communication difficulties and poor knowledge management. To overcome these problems, both current theories and empirical results suggest that problems and solution should be shared between production managers on seminars or similar. Know-how must be retained and shared between projects by developing standards for knowledge management on central level in the organisation.

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Dai, Bin. « Development of a free-ranging material handling system for manufacturing and warehouse application / ». View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?IELM%202009%20DAI.

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Thongmal, Larsson Marie. « A model for material handling improvements when using automated storage systems : A case study ». Thesis, Linnaeus University, School of Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-6350.

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The purpose of this thesis is to create a model of how to organize the placements of articles in an automated storage system in order to reduce time and cost related to the extractions. The model was developed during an investigation at a case company, and a comprehensive study of the material handling identified bottlenecks, whereof one was chosen to be further investigated: the automated storage system. The automated storage system is newly installed equipment, which required new working methods to be incorporated to the already existing working environment. The ABC-analysis was used in order to motivate how the articles should be placed in the automated storage. The goal for the new way of handling material was to put as little effort as possible on time related to the extraction of material. This due to the realization of material handling processes being a huge contributor to waste activities. This resulted in the development of the model and the suggestion that is given to the case company is to place the most frequent extracted articles close to the users. However, advantages must be held against disadvantages of rearrangements since the material handling will not be eliminated totally due to smaller improvements.

Syftet med denna uppsats är att skapa en modell för hur man ska organisera artikelplaceringar i ett automatiserat lagersystem för att reducera tid och kostnad relaterat till uttag av material. Modellen skapades genom en undersökning på ett fallföretag, en omfattande studie av materialhanteringen identifierade flaskhalsar, varav en valdes för fortsatt undersökning: det automatiserade lagersystemet. Det automatiserade lagersystemet är en nyinstallerad utrustning, som kräver att nya arbetsmetoder ska inkorporeras till den redan existerande arbetsmiljön. ABC-analysen användes för att motivera hur artiklarna ska placeras i det automatiserade lagret. Målet för det nya sättet att hantera material på var att så få insatser som möjligt skulle användas för uttag av material. Detta pågrund av insikten utav att materialhanteringsprocesser är en stor bidragande slöserifaktor. Detta resulterade i modellen och förslagen som ges till fallföretaget är att placera de mest frekvent använda artiklarna nära användaren. Emellertid så måste man väga fördelar mot nackdelar av en förändring eftersom materialhanteringen inte kommer att elimineras helt pågrund av mindre förbättringar.

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Boparai, Ramanpreet. « Integration of operation allocation and material handling in the design of flexible manufacturing systems ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ62188.pdf.

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Shen, Yu-Cheng. « The impact of vehicle dispatching on the design of multiple-transporters material handling systems ». Diss., Virginia Tech, 1995. http://hdl.handle.net/10919/40224.

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Napisa, Rodolfo R. « Conceptual design of a material handling system for a county airport mail center ». Master's thesis, This resource online, 1997. http://scholar.lib.vt.edu/theses/available/etd-12162009-020127/.

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Sivagnanavelu, Devi G. « Dynamic scheduling of flexible manufacturing systems : a study of machine and material handling control strategies ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0020/MQ47839.pdf.

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Tabatabaei, Sorour. « Numerical prediction for thixotropic and non-thixotropic material systems in complex flow ». Thesis, Swansea University, 2014. https://cronfa.swan.ac.uk/Record/cronfa43154.

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Notarberardino, Bruno. « Image based finite element modelling for the mechanical characterisation of complex material systems ». Thesis, University of Exeter, 2010. http://hdl.handle.net/10036/99354.

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There is been increasing interest in understanding the physical properties of cellular solid for designing function specific architectures. A new approach has been adopted for modelling those complex micro-systems using image based techniques. The image based meshing is a novel method capable of generating the required volume discretisation (finite element and finite volume meshes) directly and robustly from the image data obtained from a range of imaging modalities such as magnetic resonance imaging and computed tomography. The purpose of the present work is combining image based meshing with finite element method (FEM) for mechanically characterise complex micro-structures. Cellular solid, previously investigated using conventional analytical and experimental approaches and their limitations, will be now explored with the accuracy and the precision of the image based finite element approach. Analytical models of the mechanics of open cell foams are reviewed and extended into a new parametric model which includes axial compression as deformation mechanism during compression. The parametric model, supported by the novel method, is used to predict the mechanical behaviour of two regular open cell micro-structures and a topology obtained from tomographic imaging of an open celled foam. The new approach is then extended to the dynamic analysis of a Polyurethane open cell foam under large strain deformation and different boundary conditions. Bone scaffolds, having the architecture of cellular solids, are mechanically characterised and parametrically investigated. Finally the novel method is applied on two phases composite systems on which a wide range of parametric and sensitivity analysis are carried out. The potentialities of combining image based techniques with FEM are then enlighten. keywords: cellular solid, image processing, Finite Element Method, image based meshing, large strain deformation, dynamic analysis, bone scaffold, synthetic structures, Alumina-Aluminium composite, parametric model, Polyurethane open cell foam, reverse engineering, material characterisation, lattice factory.

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Lee, Moonsu. « Analytical models to evaluate system performance measures for vehicle based material-handling systems under various dispatching policies ». Diss., Texas A&M University, 2005. http://txspace.tamu.edu/bitstream/handle/1969.1/2352/etd-tamu-2005A-INEN-Lee.pdf?sequence=1.

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OKUMA, Shigeru, Tatsuya SUZUKI et Eiji KONAKA. « Safety Verification of Material Handling Systems Driven by Programmable Logic Controller : Consideration of Physical Behavior of Plants ». Institute of Electronics, Information and Communication Engineers, 2004. http://hdl.handle.net/2237/14987.

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Yemenicioglu, Ender [Verfasser]. « Data exchange for the physics-based simulation of material handling systems in the digital factory / Ender Yemenicioglu ». Magdeburg : Universitätsbibliothek, 2016. http://d-nb.info/113566207X/34.

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Choi, Soodong. « Material flow system integration in EOQ, ELSP, and Kanban production environments / ». free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9901227.

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Jansson, Anton. « Only a Shadow : Industrial computed tomography investigation, and method development, concerning complex material systems ». Licentiate thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-54880.

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The complexity of components fabricated in today's industry is ever increasing. This increase is partly due to market pressure but it is also a result from progress in fabrication technologies that opens up new possibilities. The increased use of additive manufacturing and multi-material systems, especially, has driven the complexity of parts to new heights. The new complex material systems brings benefits in many areas such as; mechanical properties, weight optimisation, and sustainability. However, the increased complexity also makes material integrity investigations and dimensional control more difficult. In additive manufacturing, for example, internal features can be fabricated which cannot be seen or measured with conventional tools. There is thus a need for non-destructive inspection methods that can measure these geometries. Such a method is X-ray computed tomography. Computed tomography utilizes the X-rays ability to penetrate material to create 3D digital volumes of components. Measurements and material investigations can be performed in these volumes without any damage to the investigated component. However, computed tomography in material science is still not a fully mature method and there are many uncertainties associated with the investigation technique. In the work presented in this thesis geometries fabricated by various additive manufacturing processes have been investigated using computed tomography. Also in this work, a dual-energy computed tomography tool has been developed with the aim to increase the measurement consistency of computed tomography when investigating complex geometries and material combinations.
MultiMatCT

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Hedberg, Daniel, et Viktor Hjärtquist. « Evaluation of AGV-systems for material handling in production. A simulation study at the rear axle assembly at Scania ». Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-177265.

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Scania är ett företag verksamt inom fordonsindustrin och är en tillverkare av lastbilar, bussar och motorer. Fordonsindustrin står inför en förändring och Scania vill vara drivande i utvecklingen. För att kunna vara det ställs krav på flexibilitet i produktionen och i denna studie har Scanias bakaxelmontering undersökts. I dagsläget används gaffeltruckar i stor utsträckning för att transportera artiklar mellan lager, plockområde och produktionslina, vilket begränsar utformningen av plockområdet. En introduktion av Automated Guided Vehicles (AGV) möjliggör en mer flexibel utformning. Studien syftar till att utvärdera AGV:er som transportelement för lastbärare. För att göra det undersöks det hur tre olika typer av AGV:er påverkar tiden med artikelbrist vid produktionslinan relativt antal som används samt hur dessa utnyttjas. Vidare undersöks det hur olika egenskaper i ett AGV-system påverkar kötiden för transporter. Egenskaperna som undersöks är AGV:ernas hastighet, av- och pålastningstid, laddningstid och batteritid. Systemet som undersöks i studien är en del av ett produktionsområde efter en planerad ombyggnation och inga jämförelser kommer göras med systemet innan ombyggnation. En simuleringsmodell har tagits fram i ExtendSim och genom den har experiment utförts för att besvara syftet. I studien har två olika typer av experiment utförts, dels experiment där antalet AGV:er var den experimentella faktorn, dels experiment enligt faktordesign där AGV-systemets egenskaper var de experimentella faktorerna. Resultaten från experimenten visar att när antalet AGV:er ökar till en viss gräns, minskar tiden med brist vid produktionslinan och funktionen för dynamisk laddning kan utnyttjas i högre grad. Utöver detta visar resultatet från experimenten enligt faktordesign att batteritid är den enskilt viktigaste egenskapen enligt de förutsättningar experimenten utfördes under. Därefter var AGV:ernas genomsnittliga hastighet den viktigaste egenskapen följt av laddningstid och av- och pålastningstid. Slutsatsen är att när antalet AGV:er ökar, minskar tiden med brist för upp till sex AGV:er av typ 1 och typ 2 samt åtta AGV:er av typ 3. Utnyttjandegraden visar att när fler AGV:er används kan funktionen för dynamisk laddning utnyttjas i högre grad, vilket gör att de är tillgängliga i större utsträckning när transportbehov uppstår. Det har också visats att antalet AGV:er som används i systemet bör vara tillräckligt för att de aldrig ska underskrida den kritiska batterinivån. Jämförelser av den totala tiden med brist vid produktionslinan mellan olika typer av AGV:er visade att typ 1 var bättre än typ 3 när lika antal AGV:er användes. Mellan typ 2 och typ 3 kunde ingen skillnad påvisas när fler än fem AGV:er användes. När fem eller färre AGV:er användes var typ 3 bättre än typ 2. En jämförelse mellan typ 1 och typ 2 visade att typ 1 var bättre när upp till fem AGV:er användes, men att det för sex AGV:er inte gick att avgöra någon skillnad.

Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet

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David, Carlsson, et Nilsson Björn. « Efficient internal material flow of boxes to gain a well-organized supply of components : A case study at Scania engine assembly ». Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-63771.

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Within manufacturing organizations, the material flow is a promoted part of the supply chain to evaluate, since it often stands for a significant part of the costs. The evaluation refers to the analysis and optimization of the material flow that arise during manufacturing of products. It can focus on very different levels, such as the material flow in a region or within a company’s internal processes. However, the material flow is concerned with the transportations, operations and storages of materials. A well-organized material flow enables organizations to cutting costs and increase competitiveness, via increased effectiveness and efficiency of operating practices. Scania operates in the automotive industry and they are constantly striving to improve their supply chain in terms of productivity and lower costs, to meet the needs of the market and gain increased competitiveness. Today, Scania engine assembly in Södertälje has operations in two main buildings, approximately one km in-between. One building is the material warehouse, and the other building is the actual assembly. In the future, the two building will be joint together. Consequently, the project logistics department of Scania engine assembly has recognized a possibility to re-organize and improve the material flows. The upcoming merge between the two buildings enables a possibility to investigate how the current material flows could be more efficient, before they are applied in the future state. The purpose of this research is to investigate and improve a material flow, box flow, within an automotive environment. A box flow is concerned with smaller components that use plastic boxes as packaging material. The objective is to derive a more efficient process for the flow of supplying boxes to the assembly building. By efficiency, it is defined as shorter total lead time, higher capacity, lower time/cost per box delivered, and a maintained or improved ergonomics during manual handling operations within the box flow. To fulfil the purpose of this research interviews, observations and data collections have been used to gain an understanding of how the current situation is managed at Scania engine assembly. Conducted benchmarking and literature research have been used to gain an understanding of how other companies in the industry, as well as departments at Scania, are managing their box flows. The findings have been analysed, where the different flow of boxes have been compared with the theoretical frame of reference as well as against each other. The conclusions of the analysis are different key factors, for better logistics efficiency, when managing a box flow. These key factors are providing an increased theoretical understanding, when the aim is to make a material flow of boxes more efficient, in an assembly environment. In this research, they are utilized as guidelines, to derive a more efficient process for the flow of supplying boxes. That is, implementing the findings theoretically into a practical context. To derive a more efficient process, a Business Case have been conducted. Its outcome provides a concept of how the process of boxes should be organized. That is, how the different material handling operations and equipment should be utilized to achieve an overall increased efficiency. How the box flow should be organized are presented as recommendations, which works as guidelines and insights for Scania engine assembly. They are jointly fulfilling the purpose of this research, together with the other achieved research questions.
Inom tillverkningsorganisationer är materialflödet en prioriterad del av försörjningskedjan att utvärdera, eftersom den ofta står för en betydande del av kostnaderna. Utvärderingen avser analys och optimering av materialflödet som uppstår vid tillverkning av produkter. Den kan fokusera på många olika nivåer, som materialflödet i en region eller inom ett företags interna processer. Materialflödet berör emellertid transporten, operationerna och materiallager. Ett välorganiserat materialflöde gör det möjligt för organisationer att sänka kostnaderna och öka konkurrenskraften, genom ökad inre- och yttre effektivitet av utföranden inom företaget. Scania verkar inom bilindustrin och strävar ständigt efter att förbättra sin försörjningskedja när det gäller produktivitet och lägre kostnader, för att möta marknadens behov och öka konkurrenskraften. Idag har Scanias motormontering i Södertälje verksamheter i två huvudbyggnader, med ca en kilometer mellan varandra. Den ena byggnaden är materiallagret, och den andra byggnaden är den faktiska monteringen. I framtiden kommer de två byggnaderna att bli integrerade. Följaktligen har projektlogistikavdelningen vid Scanias motormontering bedömt en möjlighet att organisera och förbättra deras materialflöden. Den kommande integrationen mellan de två byggnaderna gör det möjligt att undersöka hur de aktuella materialflödena kan bli effektivare, innan de appliceras i det framtida tillståndet. Syftet med denna forskning är att undersöka och förbättra ett materialflöde, boxflöde, i en monteringsmiljö. Ett boxflöde behandlar mindre komponenter som använder plastlådor som förpackningsmaterial. Målet är att klarlägga en effektivare process för flödet av boxar till monteringsbyggnaden. Effektivitet definieras som ett flöde som har kortare total ledtid, högre kapacitet, lägre tid / kostnad per box levererad och en bibehållen eller förbättrad ergonomi under manuella hanteringar. För att uppfylla syftet med forskningen har olika typer av intervjuer, observationer och datasamlingar använts, för att skapa en djupare förståelse över den nuvarande situationen hos Scanias motormontering. Genomförd benchmarking och litteraturforskning har använts för att förstå hur andra företag inom branschen, även andra avdelningar på Scania, hanterar sina boxflöden. Den insamlade empirin har använts i en analys där de olika flödena av boxar har jämförts både med den teoretiska referensramen samt varandra. Konklusionerna från analysen är presenterade som nyckelfaktorer för att öka effektiviteten vid hantering av boxföden. Dessa nyckelfaktorer ger en ökad teoretisk förståelse, när syftet är att skapa ett effektivare materialflöde i form av boxar, i en monteringsmiljö. I denna forskning används nyckelfaktorerna som riktlinjer för att skapa en effektivare process för flödet av boxar. Det vill säga, att implementera nyckelfaktorerna teoretiskt i ett praktiskt sammanhang. För att ta fram en effektivare process har ett Business Case realiserats, som presenterar hur samtliga processer inom boxflödet borde organiseras på fallföretaget. Det vill säga, hur olika materialhanteringsoperationer och utrustningar borde användas för att uppnå en ökad effektivitet som helhet. Hur boxflödet ska organiseras presenteras som rekommendationer. Dessa bidrar med insikter och riktlinjer för hur Scanias motormontering borde organiseras, gällande deras interna materialflöde. Tillsammans med resterande forskningsfrågor uppfyller rekommendationerna syftet med forskningen.

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Bäck, Daniel, et Peter Johansson. « A model for effective development of plant layouts and material handling systems : En modell för effektiv utformning av fabrikslayouter och materialhanteringssystem ». Thesis, Växjö University, School of Technology and Design, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-1306.

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In this thesis was a model developed, in order to improve deficiencies in existing literature regarding the layout problem and to give companies a comprehensible user-friendly procedure on how to design competitive production processes, plant layouts and material handling systems. The model consists of six phases that can be used sequentially in order to design, evaluate, implement and maintain effective plant layouts and material handling systems. The model can also be used to examine and optimize processes. The first four phases of the model were tested successfully in a case study at Holtab AB, a medium sized manufacturing company in Tingsryd.

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Schmidt, Thorsten, et Frank Schulze. « Simulationsbasierte Entwicklung energieeffizienter Steuerungsstrategien für Materialflusssysteme ». Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-233336.

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Die Kosten für die Energieversorgung eines Materialflusssystems übersteigen die Investitionskosten oft schon nach wenigen Jahren. Mit steigenden Energiepreisen wird dieser Zeitraum kürzer. Bei der Bewertung der Lebenszykluskosten eines Materialflusssystems rücken deshalb die Energiekosten immer mehr in den Vordergrund. Viele Möglichkeiten zur Energieeffizienz-Steigerung sind zwar bereits bekannt, jedoch wird davon meist nur punktuell, nicht aber systematisch Gebrauch gemacht. Dies gilt insbesondere für die Ebene der Anlagen- bzw. Systemsteuerung. Die Bemühungen um eine Steigerung der Energieeffizienz in der Intralogistik fokussieren bislang auf die Optimierung fördertechnischer Komponenten (Leichtbau, Antriebe). Damit wird jedoch nur das Symptom behandelt, nicht aber die Ursache: Der energetische Aufwand für Transportvorgänge – das Symptom – muss zweifellos reduziert werden. Das geschieht auch bereits. Zugleich ist aber sicherzustellen, dass zur Lösung einer konkreten logistischen Aufgabenstellung – der Ursache – Transporte nur im tatsächlich erforderlichen Umfang und in der richtigen Weise durchgeführt werden. Dafür Sorge zu tragen, ist Aufgabe einer energieeffizienten Anlagensteuerung. Die Forschungsarbeiten an der TU Dresden verfolgen drei Ziele: (a) Der Zusammenhang zwischen der mechanischen Leistung und dem elektrischen Energieverbrauch typischer Fördertechnik-Komponenten soll allgemeingültig beschrieben werden. (b) Es sollen Routinen entwickelt werden, mit denen in der ereignisdiskreten Simulation die mechanische Leistung einer Anlage und der resultierende elektrische Energieverbrauch bestimmt wird. (c) Mithilfe der Simulation soll gezeigt werden, wie und in welchem Umfang optimierte Steuerungsstrategien die Energieeffizienz von Materialflusssystemen steigern.

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Klein, Nils. « The impact of decentral dispatching strategies on the performance of intralogistics transport systems ». Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-147739.

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This thesis focuses on control strategies for intralogistics transport systems. It evaluates how switching from central to decentral dispatching approaches influences the performance of these systems. Many ideas and prototypes for implementing decentral control have been suggested by the scientific community. But usually only the qualitative advantages of this new paradigm are stated. The impact on the performance is not quantified and analyzed. Additionally, decentral control is often confused with distributed algorithms or uses the aggregation of local to global information. In the case of the latter, the technological limitations due to the communication overhead are not considered. The decentral prototypes usually only focus on routing. This paper takes a step back and provides a generic simulation environment which can be used by other researchers to test and compare control strategies in the future. The test environment is used for developing four truly decentral dispatching strategies which work only based on local information. These strategies are compared to a central approach for controlling transportation systems. Input data from two real-world applications is used for a series of simulation experiments with three different layout complexities. Based on the simulation studies neither the central nor the decentral dispatching strategies show a universally superior performance. The results depend on the combination of input data set and layout scenario. The expected efficiency loss for the decentral approaches can be confirmed for stable input patterns. Regardless of the layout complexity the decentral strategies always need more vehicles to reach the performance level of the central control rule when these input characteristics are present. In the case of varying input data and high throughput the decentral strategies outperform the central approach in simple layouts. They require fewer vehicles and less vehicle movement to achieve the central performance. Layout simplicity makes the central dispatching strategy prone to undesired effects. The simple-minded decentral decision rules can achieve a better performance in this kind of environment. But only complex layouts are a relevant benchmark scenario for transferring decentral ideas to real-world applications. In such a scenario the decentral performance deteriorates while the layout-dependent influences on the central strategy become less relevant. This is true for both analyzed input data sets. Consequently, the decentral strategies require at least 36% to 53% more vehicles and 20% to 42% more vehicle movement to achieve the lowest central performance level. Therefore their usage can currently not be justified based on investment and operating costs. The characteristics of decentral systems limit their own performance. The restriction to local information leads to poor dispatching decisions which in return induce self-enforcing inefficiencies. In addition, the application of decentral strategies requires bigger storage location capacity. In several disturbance scenarios the decentral strategies perform fairly well and show their ability to adapt to changed environmental conditions. However, their performance after the disturbance remains in some cases unpredictable and relates to the properties of self-organizing complex systems. A real-world applicability has to be called into question.

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Abrahamsen, Liam Gustav. « Development of Kinetic Speciation Models for complex Quartz Sand or Montmorillonite Ternary systems containing metal ions and humic material ». Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511858.

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Schmidt, Thorsten, et Frank Schulze. « Simulationsbasierte Entwicklung energieeffizienter Steuerungsstrategien für Materialflusssysteme ». Wissenschaftliche Gesellschaft für Technische Logistik (WGTL), 2011. https://tud.qucosa.de/id/qucosa%3A30811.

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Die Kosten für die Energieversorgung eines Materialflusssystems übersteigen die Investitionskosten oft schon nach wenigen Jahren. Mit steigenden Energiepreisen wird dieser Zeitraum kürzer. Bei der Bewertung der Lebenszykluskosten eines Materialflusssystems rücken deshalb die Energiekosten immer mehr in den Vordergrund. Viele Möglichkeiten zur Energieeffizienz-Steigerung sind zwar bereits bekannt, jedoch wird davon meist nur punktuell, nicht aber systematisch Gebrauch gemacht. Dies gilt insbesondere für die Ebene der Anlagen- bzw. Systemsteuerung. Die Bemühungen um eine Steigerung der Energieeffizienz in der Intralogistik fokussieren bislang auf die Optimierung fördertechnischer Komponenten (Leichtbau, Antriebe). Damit wird jedoch nur das Symptom behandelt, nicht aber die Ursache: Der energetische Aufwand für Transportvorgänge – das Symptom – muss zweifellos reduziert werden. Das geschieht auch bereits. Zugleich ist aber sicherzustellen, dass zur Lösung einer konkreten logistischen Aufgabenstellung – der Ursache – Transporte nur im tatsächlich erforderlichen Umfang und in der richtigen Weise durchgeführt werden. Dafür Sorge zu tragen, ist Aufgabe einer energieeffizienten Anlagensteuerung. Die Forschungsarbeiten an der TU Dresden verfolgen drei Ziele: (a) Der Zusammenhang zwischen der mechanischen Leistung und dem elektrischen Energieverbrauch typischer Fördertechnik-Komponenten soll allgemeingültig beschrieben werden. (b) Es sollen Routinen entwickelt werden, mit denen in der ereignisdiskreten Simulation die mechanische Leistung einer Anlage und der resultierende elektrische Energieverbrauch bestimmt wird. (c) Mithilfe der Simulation soll gezeigt werden, wie und in welchem Umfang optimierte Steuerungsstrategien die Energieeffizienz von Materialflusssystemen steigern.

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Baumann, Marion [Verfasser], et K. [Akademischer Betreuer] Furmans. « Discrete Time Analysis of Multi-Queue Systems with Multiple Departure Streams in Material Handling and Production under Different Service Rules / Marion Baumann ; Betreuer : K. Furmans ». Karlsruhe : KIT Scientific Publishing, 2019. http://d-nb.info/1202111920/34.

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Mokhlespour, Esfahani Mohammad Iman. « Development and Assessment of Smart Textile Systems for Human Activity Classification ». Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/97249.

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Wearable sensors and systems have become increasingly popular for diverse applications. An emerging technology for physical activity assessment is Smart Textile Systems (STSs), comprised of sensitive/actuating fiber, yarn, or fabric that can sense an external stimulus. All required components of an STS (sensors, electronics, energy supply, etc.) can be conveniently embedded into a garment, providing a fully textile-based system. Thus, STSs have clear potential utility for measuring health-relevant aspects of human activity, and to do so passively and continuously in diverse environments. For these reasons, STSs have received increasing interest in recent studies. Despite this, however, limited evidence exists to support the implementation of STSs during diverse applications. Our long-term goal was to assess the feasibility and accuracy of using an STS to monitor human activities. Our immediate objective was to investigate the accuracy of an STS in three representative applications with respect to occupational scenarios, healthcare, and activities of daily living. A particular STS was examined, consisting of a smart socks (SSs), using textile pressure sensors, and smart undershirt (SUS), using textile strain sensors. We also explored the relative merits of these two approaches, separately and in combination. Thus, five studies were completed to design and evaluate the usability of the smart undershirt, and investigate the accuracy of implementing an STS in the noted applications. Input from the SUS led to planar angle estimations with errors on the order of 1.3 and 9.4 degrees for the low-back and shoulder, respectively. Overall, individuals preferred wearing a smart textile system over an IMU system and indicated the former as superior in several aspects of usability. In particular, the short-sleeved T-shirt was the most preferred garments for an STS. Results also indicated that the smart shirt and smart socks, both individually and in combination, could detect occupational tasks, abnormal and normal gaits, and activities of daily living with greater than 97% accuracy. Based on our findings, we hope to facilitate future work that more effectively quantifies sedentary periods that may be deleterious to human health, as well as detect activity types that may be help or hinder health and fitness. Such information may be of use to individuals and workers, healthcare providers, and ergonomists. More specifically, further analyses from this investigation could provide strategies for: (a) modifying a sedentary lifestyle or work scenario to a more active one, and (b) helping to more accurately identify occupational injury risk factors associated with human movement.
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Ramde, Sara, et Lana Qadir. « Effektivisering av materialflödet i inlagringsprocessen i ett distributionslager : Genom exkludering av begränsningar ». Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Industriell organisation och produktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-41781.

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Syfte – Syftet med studien är att identifiera kritiska begränsningar i inlagringsprocessen i ett distributionslager för att därmed kunna effektivisera materialflödet. Studiens syfte uppnås genom att följande forskningsfrågor har formulerats: Vilka kritiska begränsningar kan förekomma i materialflödet i en inlagringsprocess i ett distributionslager? Hur kan de identifierade begränsningarna exkluderas i en inlagringsprocess? Metod – Studien hade en induktiv ansats och datainsamling skedde genom intervjuer, observationer, dokumentstudier och litteraturstudier. En fallstudie genomfördes på ett distributionslager och empiri och teori har jämförts för att kunna uppfylla studiens syfte. Resultat – Studiens resultat påvisar att de förekommande kritiska begränsningarna i ett distributionslager är brist på yta, materialhantering, automatiska system samt lagerlayout. Studiens slutsats är att begränsningarna är sammankopplade och påverkar varandra eftersom de ingår i samma process. För att exkludera begränsningarna bör distributionslager implementera diverse standarder i sin inlagringsprocess och arbeta med ständiga förbättringar. Implikationer – Studien bidrar inte med nya teorier men bidrar med praktisk nytta för distributionslager med liknande kriterier som studiens fallföretag. Begränsningar – Studien riktar enbart in sig på distributionslager och var en fallstudie av enfallsdesign. Genom att utföra flera liknande undersökningar på företag med liknande kriterier hade generaliserbarheten kunnat stärkas.
Purpose – The purpose of the study is to identify critical constraints in the inbound process at a distribution warehouse. To accomplish the purpose two research questions were formulated: Which critical constraints can occur in the material flow in the inbound process at a distribution warehouse? How can the identified constraints be excluded in the inbound process? Method – The study was performed inductively, and the data collection techniques were interviews, observations, document studies and literature studies. A single case study was performed at a distribution warehouse and the empirical data and theories were compared to accomplish the purpose of the study. Findings – The result of the study demonstrates that the critical constraints in the inbound process at a distribution warehouse are space, material handling, automatic systems and warehouse layout. The conclusion of the study is that the constraints are connected and affect each other since they are all included in the same process. To exclude the constraints different types of standards should be implemented in the inbound process, and distribution warehouses should work with continuous improvements. Implications – The study does not contribute to new theories but can be practically beneficial for distribution warehouses similar to the studies case study. Limitations – The study only focuses on one distribution warehouse and is therefore a single case study. The generalizability could have been higher if the study had been conducted at multiple distribution warehouses.

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Hozak, Kurt. « RFID as an enabler of improved manufacturing performance ». Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1178836596.

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Dahl, Alexander. « Product allocation for an automated order picking system in an e-commerce warehouse : A data mining approach ». Thesis, Linköpings universitet, Logistik- och kvalitetsutveckling, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-165703.

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Warehouse automation is a measure E-commerce companies can take to get a more streamlined flow through their warehouse. Order picking is the most labor intensive task in a warehouse. By automating the order picking process companies can lower their costs and improve their response times. This thesis studies the A-frame, an automated order picking system, at a large online pharmacy, Apotea AB. An A-frame has dispensing channels on its side and a conveyor belt that runs through the entire machine. Products for an order are ejected from the channels onto the conveyor belt and at the end of the machine they are dropped into a box. The box is then sealed, labeled and sent to the customer. For the automatic flow to function correctly, all orders picked by the A-frame need to be complete orders. Complete orders are orders where there are no products missing. To maximize the throughput of the A-frame, an appropriate product allocation will be required. Due to the vast number of combinations, it is extremely difficult to identify an optimal product allocation. This study has examined three different approaches to the product allocation problem for an A-frame. The first two methods are based on ranking the products depending on their quantities sold. The last method uses association rule learning, which is a machine learning technique for finding interesting patterns in a data set. Association rule learning was used to find which products were associated to each other. These associations were then placed in a graph structure and solved using a heuristic. To evaluate the different allocation methods, a simulation model was created. The A-frame was simulated using a discrete event simulation, which meant all methods could be tested on the same data to correctly compare the performance of each allocation. The study showed that the heuristic using association rules gave the highest number of picks for the tested period. However, it was only marginally better than the method that first removed orders that could not be picked from the A-frame and then ranked all products by their quantities sold. The study's conclusion is that while association rule learning resulted in the highest number of picked orders, the gain of using it does not motivate its complexity. Instead a more simple approach by ranking products by their quantities sold should be used. Warehousing in the era of E-commerce has to be fast, correct and cheap.

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Juslin, Victor, et Malin Gavlefors. « Materialhanteringens utmaningar för tillverkande företag ». Thesis, Tekniska Högskolan, Jönköping University, JTH, Logistik och verksamhetsledning, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-50075.

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Purpose – The purpose of this study is to increase the knowledge about the material handling of a module house manufacturing company. In order to achieve the study's purpose, three research questions were formulated. ▪ Which factors affect material handling? ▪ Which factors are considered important for material handling? ▪ How can standardization improve material handling? Method – The study has been characterized by an inductive approach to conducting the case study. To achieve the purpose, empirical data has been collected via a pilot study, interviews, observations, and document studies from reality. Subsequently, previous theories were examined via a literature collection. Furthermore, the processing and analysis of collected empirics and theory have helped to answer the purpose and demonstrate the generalizability of the study. Findings – The study has focused on the entirety of the various processes and an understanding of the various factors that influence material handling has been obtained. The case study company has challenges to look at the entirety of the modular house production and separates the production and construction sites. The wastes transport, movement, waiting and unused skills are considered to be the most important wastes to reduce or eliminate. It is clear that the case study company’s new employees must constantly reinvent the wheel and learn from their own mistakes. Moreover, it is difficult to determine if the mistake is a deviation, error or insufficient knowledge. By implementing a standard for what should be on drawings and how materials are to be delivered from production to the construction sites, deviations and wastes can be reduced and costs reduced. Implications – The study is based on a problem area that already exists in separate theories and comparisons. However, operations that have a material handling that both concerns manufacturing and construction work have not previously been investigated to the same extent, which is the theoretical contribution of the study. The empirical contribution to the study is to identify which factors affect material handling in businesses that have common flows between manufacturing and construction work. Limitations – The study only addresses two of the material handling flows; the material flow and the information flow. The study also does not take into account the processes of suppliers, subcontractors, or customers. Finally, the study will not include financial calculations to demonstrate potential cost efficiencies. Keywords – Material handling, Lean, Construction logistics, Wastes, Current flow, Value stream mapping, Lean tools.

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Forsén, Isak. « Materialspill i aktivt projekt : Hur ser situationen ut och kan mängden spill minskas ? » Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-185631.

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SCA Obbola är ett pappersbruk som satsar på framtiden och håller på att utöka sin produktion. Projektet kallas Expansion Obbola och fabriken planerar öka kapaciteten från 450 000 ton till 725 000 ton. Peab är utförandeentreprenad för projektet, arbetet startade år 2018 och förväntas vara färdigt till år 2023. I samarbete med Peab har ett examensarbete utförts på projektet Expansion Obbola för att ta reda på hur arbetet med materialspill ser ut i projektet i dagsläget och om möjligheten finns att minska mängden materialspill. Syftet med arbetet är att få en tydligare bild över materialspillet på projektet Expansion Obbola, för att vidare möjliggöra och utöka Peab:s arbete med materialspill på ett effektivt, ekonomiskt och miljövänligt sätt. Arbetet har även som syfte att bidra till Peab:s framtida arbete med materialspill. Vid produktionen av en ny byggnad uppskattas 30-40% av den totala kostnaden bestå av materialkostnader, vilket medför att om mängden materialspill kan begränsas kan det bidra till ett mer hållbart, ekonomiskt och miljövänligt arbete. Arbetet resulterade i att situationen på projektet Expansion Obbola består av svåra förutsättningar och att detta försvårar möjligheten till minskandet av materialspill betydligt. Tidspress, brist på ytor och begränsat med riktlinjer till hur man bör hantera materialspill är de främsta svårigheterna som projektet besitter. Efter genomförande av detta arbete anses det ändå finnas gott om utvecklingsområden för projektet gällande materialspill trots svårigheterna och några av de presenterade förslagen på hur man kan arbeta med att få en minskad mängd materialspill är följande: Ändra dag och tiden för revidering av ritningar, öka samarbetet mellan arbetsledare, byta virket vid formsättning till en lägre kvalité för att bespara på miljön samt utöka samarbetet med projektörerna. Projektet Expansion Obbola anses därav trots svåra förutsättningar, besitta goda möjligheter att förbättra sitt arbete med materialspill och potentiellt kunna minska mängden material som slängs i onödan.
SCA Obbola is a papermill that is investing in the future and is expanding its production. The project is called Expansion Obbola and they plan to increase their factory's capacity from 450,000 tonnes kraftliner to 725,000 tonnes. Peab is the contractor for the project, it started in 2018 and is expected to be completed by the year 2023. In collaboration with Peab, a report has been carried out on the Expansion Obbola project to find out how they work to minimize material waste. The report will also look into the current way of dealing with material waste and if the opportunity exists to reduce the amount of material waste even more. The purpose of the report is to get a clearer picture of the material waste on the project Expansion Obbola, to further enable and expand Peab's work with material waste in an efficient, economical and environmentally friendly way. The report also aims to contribute to Peab's future work with material waste in a positive way. During the production of a new building, it is estimated that 30-40% of total cost consists of material costs, which means that if the amount of material waste can be limited, it can contribute to a more sustainable, economical and environmentally friendly way of building. This report resulted in that the situation in project Expansion Obbola is consisting of some difficulties and that it significantly complicates the possibility of reducing the material waste. Pressured time schedule, lack of space and limited guidelines on how to handle material waste are the main difficulties that the project poses but after the completion of this report, it is still considered that there are plenty of development areas for the project regarding material waste. Some of the presented proposals on how to work to reduce the amount of material waste are: Changing the day and time for revision of drawings, increase the cooperation between supervisors, change the wood for casting to a lower quality to spare the environment and expand the collaboration with the designers. The Expansion Obbola project is therefore considered, despite difficult conditions, to have good opportunities to improve its work with material waste and potentially be able to reduce the amount of material that is thrown away unnecessarily.

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