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  • 1.
    Abid, Ali
    et al.
    Mälardalens högskola, Institutionen för innovation, design och produktutveckling. Mälardalens högskola, Akademin för innovation, design och teknik.
    Roback, Joel
    Mälardalens högskola, Institutionen för innovation, design och produktutveckling.
    Produktutveckling för Cate & Nelson Design: Framtagning av möbel2008Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Denna rapport behandlar examensarbete utfört för industridesignföretaget Cate & Nelson Design. Företaget ligger i Eskilstuna och jobbar i huvudsakligen med möbeldesign och inredningsprodukter. Projektgruppensuppgift har varit att ta fram en ny möbel för företaget och arbetet har omfattat utveckling av hela produkten från idé till prototyp.

    Fulltekst (pdf)
    FULLTEXT01
  • 2.
    Alamerison, Seif
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Tarek, Karzan
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Samverkanspelare i icke bärande fasadelement2009Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    Abstract

    The tests work is about the subject "synergism of steel and concrete."

    The construction sector is in a strong competition and the different companies in the Prefab

    Market has ever tried to develop new design solutions that are efficient and environmentallyfriendly.

    The purpose of this report is to highlight different aspects of interaction and size up a columndimension and to examine its efficiency and load capacity as Eurocode 3 and Eurocode 4. A sizing chart that describes the relationship between the torque and normal force shouldalso be made of the interaction .

     

    Fulltekst (pdf)
    FULLTEXT01
  • 3.
    Alhasan, Wahaab
    Mälardalens universitet, Akademin för innovation, design och teknik. Malardalen University.
    EVALUATING CHALLENGES, BENEFITS, AND DEPENDABILITY OF VIRTUAL AND PHYSICAL TESTING OF EMBEDDED SYSTEMS SOFTWARE2022Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Software testing is a widely used quality assurance activity and often starts from the early development stages. However, starting early in the development process raises difficulties and challenges practitioners must deal with; most typically, hardware is not available in the required quantities, and there is the risk of damaging the hardware while testing. Emulating the physical hardware into virtual versions is a popular approach to overcome the mentioned obstacles. This master thesis, carried out at Westermo AB, investigates the differences between the physical and virtual hardware used for embedded system software testing and the possible benefits of combining both hardware versions in a hybrid system. Investigating differences between the hardware options helps identify which type of tests are more suitable in physical versus virtual hardware. The selected method for this thesis is a case study, starting with a pre-study phase investigating how other industries tackle the difficulties and challenges mentioned. Further, data were collected from two sources, historical test reports, and a questionnaire. The historical test reports showed a timing difference between virtual and physical hardware. The reset process of physical hardware is often faster than virtual hardware, but the link-up/link-down time is slower in physical hardware. The questionnaire also confirmed the timing differences as a significant challenge often experienced by engineers. Another challenge highlighted by the questionnaire answers is that "false positives" are typically caused by virtual hardware, where issues do not always turn up due to the virtual nature of communication. Another difference proven from this thesis is that virtual hardware is more failure-prone during the early stages of testing than physical hardware. The hybrid system could be advantageous in various ways, such as quantitatively expanding the current test systems and increasing test coverage. Future work could contribute with a proof-of-concept implementation of the hybrid system to confirm the advantages and demonstrate the third option of a test system. 

    Fulltekst (pdf)
    fulltext
  • 4.
    Andemariam, Selam Fitsum
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    INTRODUCTION OF CYBERSECURITY INTO VERIFICATION PROCESSES FOR CONSTRUCTION EQUIPMENT: Cybersecurity Verification2024Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Technology is evolving at a very fast pace in various domains, including the construction equipment industry. Although the increased automation and connectivity in different products, such as vehicles, heavy machinery, and many others, have advantages, they also have disadvantages. The main disadvantage is that the cybersecurity vulnerabilities increase as the system’s complexity increases. At the same time, the inclusion of cybersecurity processes into the Software Development Life Cycle (SDLC) will soon be mandatory. Therefore, this thesis explores integrating cybersecurity verification processes into the SDLC at Volvo Construction Equipment (VCE). A case study was conducted using a combination of a literature study and a survey. The survey was conducted within the software verification department at VCE to assess the current state of cybersecurity awareness and identify potential strategies for improvement. The survey results indicate a need for increased awareness and education in cybersecurity verification processes. The proposed solution involves training and initiating cybersecurity processes early in the SDLC and gradually introducing them over an extended period. Introductory training sessions are recommended to emphasize the importance and urgency of including cybersecurity processes in the SDLC. A Security Software Development Life Cycle (SSDLC) is also proposed to integrate cybersecurity considerations throughout development. The thesis suggests a phased implementation approach, gradually changing to accommodate varying levels of familiarity with cybersecurity concepts.

    Fulltekst (pdf)
    fulltext
  • 5.
    Beckman, Erik
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Harenius, Linus
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Monitored Neural Networks for Autonomous Articulated Machines2020Independent thesis Advanced level (degree of Master (Two Years)), 300 hpOppgave
    Abstract [en]

    Being able to safely control autonomous heavy machinery is of uttermost importance for the conversion of traditional machines to autonomous machines. With the continuous growth of autonomous vehicles around the globe, an increasing effort has been put into certifying autonomous vehicles in terms of reliability and safety. In this thesis, we will investigate the problem with a deviation from the planned path for an autonomous hauler from Volvo Construction Equipment. The autonomous hauler has an error within the kinematic model, the feed-forward curvature-steering controller, due to a slip-effect that comes with the third wheel-axle. The deviation can especially be seen in sharp curves, where the deviation needs to be decreased in order to make the autonomous hauler more dependable and achieve an increased accuracy when following any given path. The aim of the thesis is to develop a fully functional Artificial Neural Network that has a new steering angle as output. The hypothesis for this thesis is to use an ANN to mimic the steering of a human driver, since a real driver compensates for the slipping behavior; both because the operator knows where on the road the machine is and also in the way that a human thinks many steps ahead whilst driving. This proposed ANN will have a monitor function which ensures that the steering angle command operates within its boundaries. Hence this thesis implies that it is indeed possible to ensure that the ANN performs reliably with the help of a monitor function in a simulated environment and can thus be used in dependable systems.

    Fulltekst (pdf)
    MonitoredANN_forAAH
  • 6.
    Bengtsson, Marcus
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Fundin, Anders
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Deleryd, Mats
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Salonen, Antti
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Olsson, Erik
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Funk, Peter
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Andersson, Carina
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Qureshi, Hassan
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Integrating Quality and Maintenance Development: Opportunities and Implications2010Inngår i: Proceedings of the 23rd International Congress on Condition Monitoring and Diagnostic Engineering Management (COMADEM 2010): Advances in Maintenance and Condition Diagnosis Technologies towards Sustainable Society / [ed] S. Okumura, T. Kawai, P. Chen, and R. B. K. N. Rao, 2010, s. 821-828Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Today, the drive in many organizations is to focus on reducing production costs while increasing customer satisfaction. One key to succeed with these goals is to develop and improve both quality and maintenance in production as well as quality and maintenance in early phases of the development processes. The purpose of this paper is to discuss how and motivate why research within quality and maintenance development may interact, in order to help companies meet customer demand while at the same time increase productivity. The paper is based on ideas and research perspectives of the newly formed competence group on ‘Quality- and Maintenance Development’ at the School of Innovation, Design and Engineering at the Malardalen University, Sweden. This paper elaborates on the concepts of Quality and Maintenance, its important integration, and provides some examples of ongoing research projects within the competence group.

  • 7.
    Bengtsson, Marcus
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Pettersson, Robert
    Volvo Construction Equipment Operations Eskilstuna, Eskilstuna, Sweden.
    Giliyana, San
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Salonen, Antti
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    The Importance of Using Domain Knowledge When Designing and Implementing Data-Driven Decision Models for Maintenance: Insights from Industrial Cases2024Inngår i: Lecture Notes in Mechanical Engineering, Springer Science and Business Media Deutschland GmbH , 2024, s. 601-614Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The advanced technologies available in the development of Smart Maintenance within Industry 4.0 have the potential to significantly improve the efficiency of industrial maintenance. However, it is important to be careful when deciding which technologies to implement for a given application and when evaluating the quality of the data generated. Otherwise, what should be cost-effective solutions may end up being cost-driving. The use of domain knowledge in selecting, developing, implementing, setting up, and utilizing these technologies is increasingly important for achieving success. In this paper, we will elaborate on this topic by presenting and analyzing insights from industrial cases, drawing on the authors’ extensive experience in the field.

  • 8.
    Bernström, David
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Nyström, Erik
    Mälardalens universitet, Akademin för innovation, design och teknik.
    RECOMMENDATIONS FOR A DEPENDABLE ROV SYSTEM FOR SWEDISH MARITIME RESEARCH2023Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    A Remotely Operated underwater Vehicle (ROV) faces many problems regarding dependability and most issues come during launch and recovery. The thesis looks at finding what dependability aspects shall be considered when developing a modular ROV to come up with recommendations for a system, together with a more reliable method of launching and recovering ROV’s. The area is important since it has been shown that there exists a gap in the market regarding multipurpose and dependable ROV’s. The method used in the thesis is a case study starting with a literature study to get a solid foundation to be able to conduct interviews. The interviews were structured as a semi-structured interview and the data were used to be able to find the important dependability aspects to give out a recommendation of a ROV system. The result shows the different dependability aspects that should be emphasised to ensure a safe system: Reliability, safety, confidentiality, maintainability, availability and integrity. From the recommendation, a simulation was conducted to test the stabilizing force to increase the reliability of launch and recovery. Furthermore, the different tests show that the amount of motion can be lowered by using thruster force as well as adding weight to the system. From the results it can be determined that the use of tether tension as a stabilizing factor is possible by using Dynamic Positioning (DP) to control the ROV’s thrusters to increase reliability.

    Fulltekst (pdf)
    fulltext
  • 9.
    Dahlström, Tommy
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering. Mälardalen University.
    Facilitating quality management through data mining2022Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    In this report, the topics of quality management, knowledge work, and Lean Six Sigma areexplored with the objective of identifying potential improvements that could be facilitated byData mining methods. With the purpose of exploring the topic of knowledge extraction fromfree-text data to support decision-making in manufacturing operations from a qualitymanagement perspective. Due to increased amounts of data being generated by new technologiessuch as Industrial Internet of Things, and increasingly complex production systems, newchallenges are emerging for manufacturing companies (Titmarsh, et al., 2020; Kamm, et al.,2021). These developments can potentially lead to an escalation of the demands on knowledgeworkers within quality management due to additional data processing. Such tasks have beenobserved to potentially increase cognitive load with decreased knowledge work productivity asa consequence, which is a key factor in effective quality management (Yusoff, et al., 2017). Inparticular, free-text data have been observed to be a challenge when implementing data miningmethods.The conducted research was guided by the following three research questions:RQ 1: What are the challenges of manually performed knowledge discovery in data for qualitymanagement?RQ 2: What are the potential benefits of implementing data mining methods for qualitymanagement in Lean Six Sigma companies?RQ 3: How can complex data processing tasks that include free-text analysis be improved?The topics in question were explored by utilizing peer-reviewed literature, which was verifiedby a case study carried out at a Lean Six Sigma industrial equipment manufacturer. The casestudy includes observations and interviews to gain understanding of the case company’soperations within the selected scope. In addition, an experimental solution with the objective ofimproving an inefficient process was developed using data mining methods for free-text analysis,as described in literature. Such methods are commonly referred to as text mining.During the case study, the challenges described in literature related to text mining in general, andwithin the manufacturing industry in particular, were observed and experienced first-hand.Properties such as lack of labelled data samples, imbalanced data sets, insufficient data qualitydue to varying grammar, and the common use of mixed languages make the implementation oftext mining in industrial contexts a challenge (Ittoo, et al., 2016). The achieved results confirmseveral of the challenges described in the reviewed literature. The task of pre-processing data toenable data-driven decision-making at the case company is identified as an inefficient, butnecessary task for extracting useful knowledge from the company’s collected data. In an attemptto identify potential improvements for this particular task, several different experimentalmachine learning models for text classification were developed.While the developed solutions did not show sufficient performance to enable full automation ofthe task, potentially promising solutions were discovered. Particularly the data-driven nature ofthe systematic Lean Six Sigma methodology was observed to be suitable for integrating withdata mining methods for enhanced results (Fahey, et al. 2020; Fahmy, et al. 2017). In addition,reducing non-value adding and cognitively demanding tasks could support in optimizing thecognitive load experienced by knowledge workers and allow for increased performance inquality management activities (Jalani, et al. 2015).

    Fulltekst (pdf)
    fulltext
  • 10.
    Domova, Veronika
    et al.
    ABB Corp Res, Vasteras, Sweden.;Linkoping Univ, Vasteras, Sweden.
    Aranda Muñoz, Alvaro
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering. RISE, Vasteras, Sweden.
    Vaara, Elsa
    RISE, Vasteras, Sweden.
    Edoff, Petra
    RISE, Vasteras, Sweden.
    Feel the Water: Expressing Physicality of District Heating Processes in Functional Overview Displays2019Inngår i: PROCEEDINGS OF THE 2019 ACM INTERNATIONAL CONFERENCE ON INTERACTIVE SURFACES AND SPACES (ISS '19), ASSOC COMPUTING MACHINERY , 2019, s. 229-240Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper describes an explorative design study conducted in the scope of a collaborative research project in the district heating domain. In the scope of the project, we have arranged extensive field studies at two power plants to understand the workflows, problems, and needs of industrial operators. We relied on the gained knowledge to design and develop novel visual interfaces that would communicate the overall status of the district heating system at-a-glance. We aimed at exploring potential directions and alternatives beyond conventional industrial interfaces. One particular aspect of our research was related to how the physicality of the underlying industrial processes can be expressed by purely visual means. The paper introduces three high-fidelity prototypes demonstrating the novel visualizations developed. The paper explains the design choices made, namely the relation between the selected visual encodings to the requirements of the industrial operators' tasks. Preliminary evaluation indicates industrial operators' interest in the designed solutions. Future work will incorporate an extensive qualitative evaluation on site.

  • 11.
    Eriksson, Christian
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Design Av Produktdisplay För Butik2009Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Detta projekt har haft som mål att utveckla produktdisplayer för användning i butiker i syfte att exponera produkter som smycken, solglasögon eller liknande. Projektet är utfört som ett examensarbete vid Mälardalens Högskola inom produktutveckling med inriktning formgivning.

    Bakgrunden till projektet är att företaget X-ponent vill utforska en ny marknad. Det vill säga konsumentmarknaden istället för sin vanliga inriktning på industri. X-ponent har fått förfrågningar om produktdisplayer av mindre tillverkare av smycken och säljer idag en enkel variant till dessa.

    Uppdraget har gått ut på att ta fram tre koncept på produktdisplayer ett med ett eget användningsområde; en väggdisplay, för att kunna användas vid vägg; en golv display, för användning på golvet i butiken; och en bordsdisplay, att kunna ställa på bord eller disk. Displayens syfte skulle vara att exponera produkten och locka folk att köpa varför konsument psykologi och marknadsföring i butik studerades. Även semiotik spelade stor roll i konceptens formgivning och studerades noga.

    För att ta reda på marknadens krav och egenskaper användarna ansåg vara bra och dåligt med dagens produkter utfördes en marknadsundersökning i butikerna i Tuna Park i Eskilstuna och på Dustins Elektronikmässa i Annexet i Stockholm. Även en utförlig konkurrensanalys utfördes på konkurrerande produkter.

    Under projektets gång har ett flertal produktutvecklings verktyg används som, funktionsanalys, FEMA och CAD (genom SolidWorks). Arbetsmetoden har varit att ta fram en mängd olika koncept för att sedan metodiskt sålla bort, förbättra och tillslut välja ut slutgilltliga koncept.

    För att göra bästa möjliga val använde jag mig av flera beprövade verktyg. Som Beslutsmatriser, PUGH och QFD. Utöver dessa verktyg hade jag flera diskussioner med uppdragsgivare och handledare.

    En viktig del har varit att presentera koncept som både uppfyller marknadens och uppdragsgivarens krav samtidigt som det är så hållbart för miljön som möjligt. för att göra detta möjligt studerades "sustainable design" (hållbar design).

    De slutgiltiga koncepten presenterades som renderade bilder. Dessa renderades i programmet 3D-Studio max. En säljande produktfolder skapades för att ge koncepten extra tyngd. Även en modell av väggkonceptet togs fram.

    Fulltekst (pdf)
    FULLTEXT01
  • 12.
    Felderer, M.
    et al.
    University of Innsbruck, Innsbruck, Austria; Blekinge Institute of Technology, Karlskrona, Sweden.
    Gurov, D.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Huisman, M.
    University of Twente, Enschede, Netherlands.
    Lisper, Björn
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Schlick, R.
    AIT Austrian Institute of Technology, Seibersdorf, Austria.
    Formal methods in industrial practice - Bridging the gap (track summary)2018Inngår i: Lect. Notes Comput. Sci., Springer Verlag , 2018, Vol. 11247, s. 77-81Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Already for many decades, formal methods are considered to be the way forward to help the software industry to make more reliable and trustworthy software. However, despite this strong belief, and many individual success stories, no real change in industrial software development seems to happen. In fact, the software industry is moving fast forward itself, and the gap between what formal methods can achieve, and the daily software development practice does not seem to get smaller (and might even be growing).

  • 13.
    Fentaye, Amare Desalegn
    et al.
    Department of Mechanical Engineering, Universiti Teknologi Petronas, Tronoh, Malaysia.
    Baheta, Aklilu
    Department of Mechanical Engineering, Universiti Teknologi Petronas, Tronoh, Malaysia.
    Gilani, Syed Ihtsham Ul-Haq
    Department of Mechanical Engineering, Universiti Teknologi Petronas, Tronoh, Malaysia.
    Gas turbine gas-path fault identification usingnested artificial neural networks2018Inngår i: Aircraft Engineering, ISSN 0002-2667, Vol. 90, nr 6, s. 992-999Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose – The purpose of this paper is to present a quantitative fault diagnostic technique for a two-shaft gas turbine engine applications.Design/methodology/approach – Nested artificial neural networks (NANNs) were used to estimate the progressive deterioration of single andmultiple gas-path components in terms of mass flow rate and isentropic efficiency indices. The data required to train and test this method areattained from a thermodynamic model of the engine under steady-state conditions. To evaluate the tolerance of the method against measurementuncertainties, Gaussian noise values were considered.Findings – The test results revealed that this proposed method is capable of quantifying single, double and triple component faults with asufficiently high degree of accuracy. Moreover, the authors confirmed that NANNs have derivable advantages over the single structure-basedmethods available in the public domain, particularly over those designed to perform single and multiple faults together.Practical implications – This method can be used to assess engine’s health status to schedule its maintenance.Originality/value – For complicated gas turbine diagnostic problems, the conventional single artificial neural network (ANN) structure-based faultdiagnostic technique may not be enough to get robust and accurate results. The diagnostic task can rather be better done if it is divided and sharedwith multiple neural network structures. The authors thus used seven decentralized ANN structures to assess seven different component faultscenarios, which enhances the fault identification accuracy significantly.

  • 14.
    Fentaye, Amare Desalegn
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Baheta, Aklilu
    Syed, Gilani
    Gas path fault diagnostics using a hybrid intelligent methodfor industrial gas turbine engines2018Inngår i: Journal of the Brazilian Society of Mechanical Sciences and Engineering, ISSN 1678-5878, E-ISSN 1806-3691, Vol. 40, artikkel-id 578Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    There are many challenges against an accurate gas turbine fault diagnostics, such as the nonlinearity of the engine health,the measurement uncertainty, and the occurrence of simultaneous faults. The conventional methods have limitations ineffectively handling these challenges. In this paper, a hybrid intelligent technique is devised by integrating an autoassociativeneural network (AANN), nested machine learning (ML) classifiers, and a multilayer perceptron (MLP). The AANNmodule is used as a data preprocessor to reduce measurement noise and extract the important features for visualisation andfault diagnostics. The features are extracted from the bottleneck layer output values based on the concept of the nonlinearprincipal component analysis (NLPCA). The nested classifier modules are then used in such a manner that fault and no-faultconditions, component and sensor faults, and different component faults are distinguished hierarchically. As part of the classification,evaluation of the fault classification performance of five widely used ML techniques aiming to identify alternativeapproaches is undertaken. In the end, the MLP approximator is utilised to estimate the magnitude of the isolated componentfaults in terms of flow capacity and isentropic efficiency indices. The developed system was implemented to diagnose up tothree simultaneous faults in a two-shaft industrial gas turbine engine. Its robustness towards the measurement uncertaintywas also evaluated based on Gaussian noise corrupted data. The test results show the derivable benefits of integrating twoor more methods in engine diagnostics on the basis of offsetting the weakness of the one with the strength of another.

  • 15.
    Fentaye, Amare Desalegn
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Univ Teknol PETRONAS, Dept Mech Engn, Perak, Malaysia.
    Gilani, Syed
    Univ Teknol PETRONAS, Dept Mech Engn, Tronoh 31750, Perak, Malaysia.
    Baheta, Aklilu
    Univ Teknol PETRONAS, Dept Mech Engn, Tronoh 31750, Perak, Malaysia.
    Gas turbine gas path diagnostics:: A review2016Inngår i: MATEC Web of Conferences 74, 00005, 2016, Vol. 74, artikkel-id 00005Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this competitive business world one way to increase profitability of a power production unit is to reduce the operation and maintenance expenses. This is possible if the gas turbine availability and reliability is improved using the appropriate maintenance action at the right time. In that case, fault diagnostics is very critical and effective and advanced methods are essential. Gas turbine diagnostics has been studied for the past six decades and several methods are introduced. This paper aims to review and summarise the published literature on gas path diagnostics, giving more emphasis to the recent developments, and identify advantages and limitations of the methods so that beginners in diagnostics can easily be introduced. Towards this end, this paper, identifies various diagnostic methods and point out their pros and cons. Finally, the paper concludes the review along with some recommended future works.

  • 16.
    Fentaye, Amare Desalegn
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Department of Mechanical Engineering, Universiti Teknologi Petronas, Tronoh, Malaysia.
    Gilani, Syed
    Department of Mechanical Engineering, Universiti Teknologi Petronas, Tronoh, Malaysia.
    Baheta, Aklilu
    Department of Mechanical Engineering, Universiti Teknologi Petronas, Tronoh, Malaysia.
    Yi-Guang, Li
    Department of Aerospace, Transport and Manufacturing, Cranfield University, Cranfield, UK.
    Performance-based fault diagnosis of agas turbine engine using an integratedsupport vector machine and artificialneural network method2019Inngår i: Proceedings of the Institution of mechanical engineers. Part A, journal of power and energy, ISSN 0957-6509, E-ISSN 2041-2967, Vol. 233, nr 6, s. 786-802Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An effective and reliable gas path diagnostic method that could be used to detect, isolate, and identify gas turbinedegradations is crucial in a gas turbine condition-based maintenance. In this paper, we proposed a new combinedtechnique of artificial neural network and support vector machine for a two-shaft industrial gas turbine engine gaspath diagnostics. To this end, an autoassociative neural network is used as a preprocessor to minimize noise and generatenecessary features, a nested support vector machine to classify gas path faults, and a multilayer perceptron to assess themagnitude of the faults. The necessary data to train and test the method are obtained from a performance model of thecase engine under steady-state operating conditions. The test results indicate that the proposed method can diagnoseboth single- and multiple-component faults successfully and shows a clear advantage over some other methods in termsof multiple fault diagnosis. Moreover, 5-8 sets of measurements have been used to assess the prediction accuracy, andonly a 2.3% difference was observed. This result indicates that the proposed method can be used for multiple faultdiagnosis of gas turbines with limited measurements.

  • 17.
    Fentaye, Amare Desalegn
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    An intelligent data filtering and fault detectionmethod for gas turbine engines2020Inngår i: MATEC Web of Conferences 314, 2020, Vol. 314, artikkel-id 02007Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In a gas turbine fault diagnostics, the removal of measurementnoise and data outliers prior to the fault analysis is very essential. Theconventional filtering methods, particularly the linear ones, are notsufficiently accurate, which might possibly lead to the loss of criticallyimportant features in the fault analysis process. Conversely, the recordedaccuracies obtained from the non-linear filters are promising. Recently, thefocus has been shifted to the artificial neural network (ANN) based nonlinearfilters due to their capability of providing a robust identity map between theinput and output data, which can be efficiently exploited in the process offault diagnosis. This paper aims to present combined auto-associative neuralnetwork (AANN) and K-nearest neighbor (KNN) based noise reduction andfault detection method for a gas turbine engine application. The performanceof the developed method has been evaluated using data obtained from amodel simulation. The test results revealed that the developed hybrid methodis more effective and reliable than the conventional methods for the faultdetection of the gas turbine engine with negligible false alarms and misseddetections.

    Fulltekst (pdf)
    fulltext
  • 18.
    Fentaye, Amare Desalegn
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Univ Teknol PETRONAS, Dept Mech Engn, Bandar Seri Iskandar, Malaysia.
    Syed, Gilani
    Univ Teknol PETRONAS, Dept Mech Engn, Bandar Seri Iskandar, Malaysia.
    Baheta, Aklilu
    Univ Teknol PETRONAS, Dept Mech Engn, Bandar Seri Iskandar, Malaysia.
    Ahmed, Mojahid
    Univ Teknol PETRONAS, Dept Mech Engn, Bandar Seri Iskandar, Malaysia.
    Two-shaft stationary gas turbine engine gas path diagnostics using fuzzy logic2017Inngår i: Journal of Mechanical Science and Technology, Vol. 31, nr 11, s. 5593-5602Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Our objective was to develop a Fuzzy logic (FL) based industrial two-shaft gas turbine gas path diagnostic method based on gas pathmeasurement deviations. Unlike most of the available FL based diagnostic techniques, the proposed method focused on a quantitativeanalysis of both single and multiple component faults. The data required to demonstrate and verify the method was generated from asimulation program, tuned to represent a GE LM2500 engine running at an existing oil & gas plant, taking into account the two mostcommon engine degradation causes, fouling and erosion. Gaussian noise is superimposed into the data to account measurement uncertainty.Finally, the fault isolation and quantification effectiveness of the proposed method was tested for single, double and triple componentfault scenarios. The test results show that the implanted single, double and triple component fault case patterns are isolated with anaverage success rate of 96 %, 92 % and 89 % and quantified with an average accuracy of 83 %, 80 % and 78.5 %, respectively.

  • 19.
    Fridholm, Victoria
    Mälardalens högskola, Akademin för innovation, design och teknik.
    IMPROVE MAINTENANCE EFFECTIVENESS AND EFFICIENCY BY USING HISTORICAL BREAKDOWN DATA FROM A CMMS: Exploring the possibilities for CBM in the Manufacturing Industry2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Purpose: Explore how historical data from a CMMS can be used in order to improve maintenance effectiveness and efficiency of activities, and investigate the possibilities for CBM in the manufacturing industry in the context of digitalization. 

    Research questions: RQ1: To what extent could condition-based maintenance or other maintenance types being used in order to predict, prevent or in other way eliminate historical breakdowns/faults? 

    RQ2: Which significance has an organization's degree of maturity to reduce the number of breakdowns? 

    Method: A case study was performed at Volvo Construction Equipment Operations in Eskilstuna, who manufactures machinery for the construction industry. The case study was compiled in two phases. Phase one was a quantitative study where raw data were collected from a CMMS and tabulated in order to later perform in-depth analysis. Phase two was designed to collect information that generated a wider understanding of the research area, by performing interviews and observations. A literature study was performed to compare the empirical findings with peer-reviewed information to ensure the quality of the study. The data is compiled and analyzed with an abductive approach. The analysis was followed by a discussion of how the research findings could support identifying possibilities of different maintenance types in the future. 

    Conclusion: The result showed that using historical breakdown data from a CMMS can be useful in order to identify organization’s current state and what possibilities different maintenance types have to decrease the number of breakdowns. To what extent the breakdowns can be decreased relies not only on the maintenance type but also an organizations maturity level. The case study´s result showed that by combining different maintenance types and increasing degree of maturity, Volvo could decrease the historical breakdowns with 86,5%. By only using CBM with current maturity level, 56% of the historical breakdowns could be predicted. However, to decide how many breakdowns that is cost-effective to prevent and precisely what maintenance type that should be used requires a cost analysis which this study is not covering. 

    Fulltekst (pdf)
    fulltext
  • 20.
    Gopalakrishnan, Maheshwaran
    et al.
    Chalmers Univ Technol, Dept Ind & Mat Sci, Gothenburg, Sweden..
    Skoogh, Anders
    Chalmers Univ Technol, Dept Ind & Mat Sci, Gothenburg, Sweden..
    Salonen, Antti
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Asp, Martin
    Volvo Grp Truck Operat, Skövde, Sweden..
    Machine criticality assessment for productivity improvement Smart maintenance decision support2019Inngår i: International Journal of Productivity and Performance Management, ISSN 1741-0401, E-ISSN 1758-6658, Vol. 68, nr 5, s. 858-878Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose The purpose of this paper is to increase productivity through smart maintenance planning by including productivity as one of the objectives of the maintenance organization. Therefore, the goals of the paper are to investigate existing machine criticality assessment and identify components of the criticality assessment tool to increase productivity. Design/methodology/approach An embedded multiple case study research design was adopted in this paper. Six different cases were chosen from six different production sites operated by three multi-national manufacturing companies. Data collection was carried out in the form of interviews, focus groups and archival records. More than one source of data was collected in each of the cases. The cases included different production layouts such as machining, assembly and foundry, which ensured data variety. Findings The main finding of the paper is a deeper understanding of how manufacturing companies assess machine criticality and plan maintenance activities. The empirical findings showed that there is a lack of trust regarding existing criticality assessment tools. As a result, necessary changes within the maintenance organizations in order to increase productivity were identified. These are technological advancements, i.e. a dynamic and data-driven approach and organizational changes, i.e. approaching with a systems perspective when performing maintenance prioritization. Originality/value Machine criticality assessment studies are rare, especially empirical research. The originality of this paper lies in the empirical research conducted on smart maintenance planning for productivity improvement. In addition, identifying the components for machine criticality assessment is equally important for research and industries to efficient planning of maintenance activities.

  • 21.
    Grönlund, Kristian
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Utveckling av heltäckande gångbord2009Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This thesis work is a 30hp D-level assignment in design as a co-operation between MälardalenUniversity and Scania CV AB in Södertälje. The purpose was to develope a close fitted catwalk.The market has seen an increasing value for these types of applications and have the ambition to keep up with the rest of the competitors. The catwalks of todays standards shall be estetical attractive, have a non slippery surface and be costefficient.While working with this project I have spent a lot of time with the concept proposals and with the evaluation of the concepts, resulting in a final CAD model and a approximation of the cost estimate. The new catwalk fulfils all the new recommendations and rules as sharp edges, ADR, the height of the stepup and a non slippery surface with built in drainage.

    Fulltekst (pdf)
    FULLTEXT01
  • 22.
    Hlebnikovs, Andrew
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Kövamees, Axel
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Do not let bad maintenance ruin your day: A case study of coordinating turnaround maintenance in a continuous flow process industry.2022Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The uptime of machinery in continuous flow process industries such as steel manufacturing plants puts pressure on the maintenance function. This in turn contributes to sustaining reliable physical assets. As absence of reliable physical assets highly affects the competitive advantage. Turnaround maintenance is a common practice in such production setups and requires top-of-the-line managerial attention to be planned,executed and assessed in an efficient manner. By applying an abductive approach and combining the qualitative and quantitative research approaches, this thesis aims to explore the managerial issue of coordinating turnaround maintenance within a continuous flow process industry. The research questions that guide this thesis consist of describing how turnaround maintenance can be coordinated and its associated challenges. By comparing publicly available literature and empirical evidence provided by performing a case study, it is confirmed that the main challenges for conducting efficient turnaround maintenance comes down to the management in all stages associated with the turnaround. To coordinate turnaround maintenance activities in the most efficient manner, several challenges must be overcome. Aligning organisational goals and generating management commitment is the first prerequisite before any improvements can be done. It is necessary to define a common scope that strives for creating reliable physical assets to enhance the competitive advantage. The defined challenges in coordination are related to before, during and after the turnaround execution. These relate to creating a cyclical process for the turnaround where previously acquired knowledge is used for improving future turnarounds. While detailed planning is necessary for each turnaround, a high level of contingency is also necessary. To achieve this and succeed, it is argued that a high level of visibility during the turnarounds and the use of standardised methods is required.

    Fulltekst (pdf)
    fulltext
  • 23.
    Hyttsten, Andreas
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Alm, Sebastian
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Integrering av ToolTracker i X-ponentskåp2010Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Följande rapport redogör för det utvecklingsarbete som hade som målbild att kombinera två produkter från X-ponent Stålinredningar AB, nämligen ordning-och-reda-systemet ToolTracker och ett verktygsskåp benämnt X-102.

    Detta utvecklingsarbete pågick under kursen KPP305, Examensarbete Produktutveckling, på Mälardalens högskola.

    Uppdragsgivaren X-ponent Stålinredningar AB hade under en tid utvecklat det intelligent ordning-och-reda-system, ToolTracker, och genom en efterfrågan på marknaden har företaget känt ett behov av att vidareutveckla detta system och placera detta i ett verktygsskåp.

    Denna produkt skulle fungera så att användaren loggar in i systemet via en RFID-läsare placerad på utsidan av skåpet, och samtidigt som en godkänd inloggning sker så låses skåpet upp automatiskt och användaren får tillgång till de verktyg som finns i skåpet. Väljer användaren att checka ut ett verktyg registreras tidpunkt för detta samt vem som tagit verktyget i systemets databas för att möjliggöra spårning av verktyget.

    De direktiv som företaget gav för projektet var att det befintliga ToolTracker-systemet skulle verka på samma sätt som tidigare, vilket gav avgränsningar mot att påverka ToolTracker-systemet.

    De problem som skulle lösas var således hur ToolTracker-systemets komponenter skulle placeras i skåpets utrymme, samt hur låskonstruktionen skulle utformas för att uppfylla de krav som ställts. De viktigaste funktioner som låskonstruktionen var tvungen att inneha, var att kunna låsa upp skåpet automatiskt vid inloggning, skåpet ska låsas automatiskt då dörren stängs samt att låset skulle kunna låsas upp manuellt. Dessa krav samt ytterligare en mängd krav kunde formuleras i den kravspecifikation som togs fram och låg som grund för arbetet. Ett genomgående viktigt krav i hela arbetet var att förändra det ursprungliga skåpet så lite som möjligt.

    När kraven tydliggjorts kunde en mängd idéer tas fram och utvecklas vidare till fullgoda koncept. Dessa koncept togs därefter genom en process där koncepten utvecklades och därefter bedömdes efter lämplighet för att sedan utvärderas och ett val av slutligt koncept skedde utifrån resultaten av dessa moment. Det vinnande konceptet uppfyllde de viktiga kraven på funktioner samt hade en väldigt liten påverkan på skåpets ursprungliga konstruktion, vilket var stora bidragande orsaker till att detta koncept valdes. Detta koncept modelleras sedan upp fullständigt med hjälp av CAD-verktyget SolidWorks för att lösa de kvarstående frågetecknen kring hur monteringen av komponenter o.s.v. skulle ske.

    Det slutliga konceptet har ett elektriskt slutbleck som låses upp då en signal läggs på, denna signal kommer då en inloggning sker i RFID-läsaren. Den automatiska låsningen av dörren sker genom att slutbleckets fall är öppet tills dörren stängs och skåpet påverkar fallet till låst läge. Den manuella öppningen sker genom den ursprungliga espanjolettlösningen.

    Analysen av resultatet säger att konceptet uppfyller de krav som ställts upp och besvarar de problemformuleringar som legat till grund för detta arbete. Målet kan därför ses som uppfyllt.

    Slutsatsen av projektet är att arbetet uppfyllde de mål som satts angående problemformuleringen, målet att ta fram en prototyp uppfylldes inte men en CAD-modell att möjliggöra detta i framtiden har tagits fram. En fortsättning på detta arbete bör därför innehålla en framtagning av en fysisk prototyp, för att verifiera att teorin och praktiken överensstämmer på ett tillfredsställande vis.

    Fulltekst (pdf)
    FULLTEXT01
  • 24.
    Jarl, Robin
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Hellsing, Robin
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Konstruktion av MC-släp2009Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Denna rapport beskriver ett projekt där målet är att skapa konstruktionsunderlag för en prototyp avett MC‐Släp, en släpvagn som dras av en motorcykel. Prototypen skulle testas med avseende påhållfasthet genom datorsimulering. Prototypen skulle också kunna användas för utställningsändamål.

    Projektet fortlöpte i huvudsak under höstterminen 2008 och är ett examensarbete för Civilingenjörinom Produktutveckling på Mälardalens Högskola.

    Uppdragsgivaren Nyzells MetallGjuteri AB hade en idé om ett egentillverkat MC‐släp som med smartuppbyggnad kan kombineras i många variationer och på så sätt ha en konkurrensfördel på marknaden.Deras kompetens inom aluminiumgjutning gjorde att de valde att släpet till stora delar skulle gjutas ialuminium, något som är unikt för denna slags produkt. Då gjutningen sker med sandgjutning så finnsstora möjligheter att anpassa varje släp och göra dessa unika utifrån specifika kundönskemål.

    Projektets mål att skapa ett konstruktionsunderlag för en prototyp, styrdes av ett antal krav frånuppdragsgivaren, men även från Vägverkets författningar. Krav på funktionalitet och viss utformningställdes av uppdragsgivaren, därtill kom krav på storlek och vikt ställda av Vägverket.

    Direktiven var att ta fram konstruktionsunderlag för två olika varianter av släp, både ett vanligttvåhjuligt släp och ett mer ovanligt enhjuligt släp. Det enhjuliga släpet kan med en fast koppling tillmotorcykeln framföras i frifart, endast begränsad av hastighetsbegränsningen som gäller. Till dessavarianter skulle två olika stilar på kåpor tas fram, en som passar glidarmotorcyklar och en som passartouringmotorcyklar. Till dessa kåpor skulle även matchande skärmar tas fram.Hjulupphängningen skulle vara av enkel typ och endast fjädrade med gummikuddar. Detta för att hållanere kostnaden och antalet delar i konstruktionen. Det finns inga krav från någon myndighet att släpskall vara fjädrade.

    Ett antal koncept togs fram av helhetsstilen för släpet och därefter valdes det bästa konceptet.Konceptet delades upp i ett antal olika delsystem och till varje delsystem togs ett grundkoncept frampå en eller flera lösningar. Dessa koncept utvecklades till färdiga delsystem. Därefter specificeradesdelsystemen och en konstruktionsplan gjordes. Därefter fick varje del en översikt på detaljnivå och allamått och toleranser sattes när delarna ritades från grunden i SolidWorks.

    Resultat blev en välbyggd prototyp som fungerar väl som utställningsföremål för att visa upp hurslutprodukten kommer att se ut och vara uppbyggd. Uppdragsgivaren uppskattade resultatet väldigtmycket.

    Analysen visar att alla delar uppfyller de krav och målvärden som fanns, inom rimliga gränser ochmålet för projektet kan anses uppnått.

    Slutsatsen var att arbetet gick bra, då projektet uppnådde sitt mål. Dock måste det poängteras tilluppdragsgivaren att tester av prototypen är mycket viktiga och det finns saker uppdragsgivaren måstese över innan en produktion kan starta.

    Fulltekst (pdf)
    FULLTEXT01
  • 25.
    Jumana, Qanadilo
    Mälardalens universitet, Akademin för innovation, design och teknik.
    LINKING OPERATIONAL SCENARIOS TO GIVEN-WHEN-THEN REQUIREMENTS2023Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    In manufacturing, requirements are an essential aspect of the development process. A requirements view provides a perspective on how requirements are incorporated into the design and architecture of a system. Requirements documents for different product versions at a company like Alstom contain operational scenarios and Given-When-Then requirements, a specific format for expressing functional requirements. Operational scenarios are examples of how the product will be used in real-world situations, and they can also be useful for identifying and specifying functional and nonfunctional requirements. Currently, operational scenarios are manually linked to Given-When-Then requirements. This thesis presents a conceptual design that streamlines the requirements engineering process and allows for easier linking operational scenarios to Given-When-Then requirements. 

    Fulltekst (pdf)
    fulltext
  • 26.
    Kinisjärvi, Robert
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Implementing FMEA for Scaling Start-ups: A Case Study of Adaptation for Overcoming Novel Technology Challenges2023Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    A start-up cannot simply be considered a smaller version of an established company. They often rely on short and informal development processes because they lack data and experience from implementing similar projects in the past. These factors are among those that lead to lower success in organizational performance and new product launches. The NPD process is well researched, but these studies are often on larger companies, and the applicability for start-ups is highly questionable. One of these NPD tools is the FMEA.

    FMEA has been proven and established for decades in various industries. However, these success scenarios often depend on sufficient resources in terms of staff and project budget. Start-ups often lack the resources to deal with major NPD project failures, which can be disastrous for their survival in their market.

    Despite the innovative benefits and economic growth that start-ups contribute to when they are successful with their NPD projects, there is little research on how established tools for large companies should be adapted. Therefore, these research questions were formulated to fill the gap in the current FMEA method:

    RQ1: What are the challenges for start-ups when implementing FMEA? RQ2: How can FMEA implementation be adapted for start-ups overcoming novel technology challenges? 

    The study consisted of a literature review and a case study. The literature review examined the key factors for FMEA implementation and the differences between start-ups and established companies. The challenges for start-ups implementing FMEA were the central question of the literature review.

    The case study was conducted in a start-up company. An adapted FMEA method and template were created there. A workshop and ten interviews were held with a variety of representatives.

    The results show that the biggest challenge for start-ups implementing FMEA is that it is too complex, unclear, and often too extensive. This can be changed by simplifying the FMEA, focusing on the critical risks, and ensuring that the sessions are not too long.

    The proposed FMEA method is easier to use with a simplified risk assessment and fewer columns. It was found that it also is equally important to train users, hold short meetings, and limit the size of each FMEA session.

    Fulltekst (pdf)
    fulltext
  • 27.
    Kuduzovic, Lejla
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Förslag till framtagning av kvalitetssäkringsrutiner för induktionshärdade drivaxlar vid Volvo CE Component Division: Examensarbete, produktutveckling, 30 poäng Avancerad nivå2008Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Detta examensarbete har handlar om att ta fram kvalitetssäkringsrutiner för induktiva värmebehandlingsmetoder mot det nya mätlabbet i samband att kvalitetssäkra produktionen av drivaxlar på Volvo Component Division. Uppgiften betyder att visa hur kvalitetssäkringen av både processen och tillverkningen ska ske genom att förebygga att fel uppstår. Huvudsaken är inte hur problemet blir löst, istället kommer koncentration lagts på metoden.

     

    Det övergripande syftet med examensarbetet är att försöka hjälpa personalen i företaget komma fram till förslag och konkreta resultat i form av kvalitetssäkringsrutiner för att förbättra både produktionen och den befintliga produktutvecklingsprocessen.

    Främsta målet är att bygga upp en fungerande kvalitetssäkring av induktiv värmebehandling inom Component Division genom att ta fram kvalitetssäkringsrutiner som stödjer metoden. Dessa rutiner skall bygga på önskemål från kunden, detta framför allt i form av beställningsblanketter, instruktioner och checklistor.

     

    Volvo Construction Equipment AB Component Division Eskilstuna arbetar idag med en kontinuerlig process- och produktförbättring med avseende på att förebygga eventuella kvalitetsbristerna. Meningen är att man i samband med den nya utbyggnaden av fabriken, nya maskiner och ny utrustning också ska bygga ett nytt materiallabb där materialprovbitar skall kunna skickas in av operatören/teknikern för olika kvalitetsundersökningar.

    I dagsläget har man börjat producera drivaxlar enligt den nya flödesgruppen vars förutsättning är att artiklarna skall tillverkas från råämne till monteringsklara detaljer. För att få ut ett smidigt produktionsflöde och optimera produktionen inom flödesgruppen måste alla parametrar och faktorer stämma på båda sidorna. Detta fås genom ständiga förbättringar samt statistiska styrningar av processen genom kontroller, underhåll och uppföljningar.

     

    Examensarbetet har till följd därav resulterat i instruktioner som beskriver kontrolleringar och provtagningar av värmebehandlade artiklar i cell07 som en åtgärd för att bygga en fungerande kvalitetssäkring av induktionshärdade artiklar på CMP. För att detta kvalitetsarbete skall ge resultat bör operationsbeskrivningen mätinstruktioner följas av samtliga på avdelningen.

    Därför är det viktigt att när ett kvalitetsproblem väl har identifierats skall nästa steg vara att gå vidare med att försöka bena ut orsakerna till problemet och hitta lösningar till dessa för att undvika eller förebygga att samma sak händer nästa gång.

     

    Fulltekst (pdf)
    FULLTEXT01
  • 28.
    Källung, Patrik
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Staaf, Pontus
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Eurocodes: Beräkningsjämförelser mellan eurocodes och BKR2008Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    In the year 2010 a transition will take place here in Sweden from the present rules how to dimension buildings in to the common rules with have been developed in Europe, the Eurocodes. Eurocode is the term for a collection standard that contains calculation rules in how to dimension constructions and buildings. They are developed by the European standardize committee.

    The purpose with this examination work is to get an insight of what changes this will contribute to, and how it will affect the dimensioning. Are there going to be any differences in the dimension you finally chose?

    To investigate these possible differences two constructions will be calculated first in the present Swedish rules, and then in the coming eurocodes.

    One of these two constructions will be build completely in steel, while the other will be build completely in concrete. The steel building will have a beam and a column dimensioned, the concrete building will likewise have a beam and a column dimensioned. To reach as equivalent comparison as possible will the same load, geometry and circumstance prevail for both standards. Limitation has been done to only dimensioning the beam and the column who is most charged.

    After we performed the calculations we could make the conclusion that dimensioning with Eurocode a higher efficiency was received, a 10 % higher efficiency on the materials. The strength of the material is with calculations with Eurocode higher, and so are the loads. One of the reasons for this is that the securityclass is added to the loads in Eurocodes and are drawn off from the strength of the materials in BKR.

    Fulltekst (pdf)
    FULLTEXT02
  • 29.
    Lagrosen, Yvonne
    Högskolan Väst, Avdelningen för Industriell ekonomi, Elektro- och Maskinteknik.
    The Quality Café: developing the World-Café method for organizational learning by including quality management tools2019Inngår i: Total Quality Management and Business Excellence, ISSN 1478-3363, E-ISSN 1478-3371, Vol. 30, nr 13-14, s. 1515-1527Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The purpose of this study was to examine the possibility of integrating the World Café method with the affinity diagram tool from quality management. The proposed combination is called the Quality Café. Quality Cafés were carried out at seven spa hotels, one municipality and two student organisations. The cafés were assessed with feedback seminars and questionnaires. The findings show that the method was appreciated by the participants. It contributed to profound dialogues with deepening insights, which stimulated creativity, increased understanding for quality issues and allowed a more holistic view. In addition, the method was experienced as enjoyable and in itself creating coherence. The findings were related to organisational learning theory and several connections were found. The Quality Café should be a useful method for researchers in social science as well as for practitioners. A limitation is that determining the specific effects of the Quality Café method compared to the original World Café is difficult.

  • 30.
    Lagrosen, Yvonne
    et al.
    Högskolan Väst, Avdelningen för Industriell ekonomi, Elektro- och Maskinteknik.
    Axgärde, Åsa
    Högskolan Väst, Avdelningen för Matematik, Data- och Lantmäteriteknik.
    External customer satisfaction through team-development based on appreciative inquiry2017Konferansepaper (Fagfellevurdert)
  • 31.
    Lagrosen, Yvonne
    et al.
    Högskolan Väst, Avdelningen för maskinteknik och naturvetenskap.
    Travis, Frederick
    Maharishi Univ Management, Ctr Brain Consciousness & Cognit, Fairfield, IA USA.
    Developing a neuropsychological measurement to capture workplace learning2016Inngår i: Journal of Modelling in Management, ISSN 1746-5664, E-ISSN 1746-5672, Vol. 11, nr 3, s. 783-801Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose - The purpose of the paper is to examine variables to be included in a measurement instrument which measures workplace learning related to recent research into quality management and brain functioning. Design/methodology/approach - A literature review was conducted, investigating measures of workplace learning as well as the connections between brain functioning and management. Further studies will use the brain integration scale to compare levels of brain integration with measures of workplace learning. Findings - The variables “empathy”, “presence and communication”, “continuity”, “influence”, “development”, “work-integrated learning” and “flow” were found to be relevant from the literature review to be tested for inclusion in the measurement instrument. A measurement model with these variables included has been developed. Research limitations/implications - This paper is conceptual in its nature. Empirical studies are needed to validate the propositions. Practical implications - The proposed measurement instrument can be used by managers to gain insight into underlying mechanisms in the organizational culture that influence employees’ learning and potential for development. Thus, it can aid managers to achieve profound learning in their organizations, which is necessary for continuously maintaining high quality of products and services. Social implications - For society, the implementation of the proposed measurement instrument in companies could lead to better health and higher job satisfaction among employees. Originality/value - Traditional ways of measuring working environment are rarely connected to brain functioning of the employees. Only requiring small resources, this approach adds to an understanding of underlying mechanisms.

  • 32.
    Lindgren, Victoria
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Josefsson, Johanna
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Samspelet mellan förebyggande underhåll och operatörsunderhåll2023Independent thesis Advanced level (degree of Master of Fine Arts (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Industrial maintenance has been recognized over the years as a potential area of development that can be improved to maintain competitiveness in the market. Maintenance is considered an important element that extends the life of an equipment, increases the safety of operators, and reduces economic losses. Neglected maintenance can lead to machinery becoming inoperable and cause process downtime and production losses. To achieve a successful maintenance outcome, a maintenance strategy should also be successfully formulated. In the following way, maintenance can be organized to ensure that equipment is restored to its original condition in the right way and at the right time. In addition, a maintenance process is dependent on a maintenance management system that plans for maintenance activities to be carried out in a systematic way. The problem with unplanned maintenance is that the main work of management and operators is negatively affected when the priority needs to shift to re-planning and restoring machines to their original condition. 

    The study is in collaboration with Outokumpu Nyby. The purpose of the study is to investigate how a company can work with strategic development of its operator maintenance. The research questions linked to the purpose are: 

    Q1: What factors should be considered in the strategic development of operator maintenance? 

    Q2: What challenges can be faced in the strategic development of operator maintenance? 

    During the study, an overall understanding of maintenance problems was created through literature studies. Then a problem area could be formulated and in connection with that the purpose and questions of the study. A qualitative approach was applied to the study as it was suitable to investigate the maintenance strategies of the case company. In addition, the qualitative approach was applied because the qualitative approach is in line with the intention of the study to contribute to greater knowledge. Using observation, a deeper understanding could be formed by seeing the production. In addition, interviews were used to collect data to get the perspective of management and operators. 

    The study resulted in implementing five factors that can contribute to the strategic development of operator maintenance. The five factors were planning, 5s, rounds, communication and motivation and commitment. Challenges with strategic development are that there is a lack of leadership, insufficient resources and that the organization wants to have a fully developed strategy before it is used. 

    The study concludes that the identified factors can be implemented to improve the work with strategic development of operator maintenance. In addition, it is crucial to focus on the totality of a maintenance strategy when formulating the strategic development of the case company's existing and substandard strategy. 

    Keywords: Maintenance, Maintenance strategy, Maintenance planning, Operator maintenance, Preventive maintenance, Corrective maintenance.

    Download (pdf)
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  • 33.
    Memic, Zijah
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Kartläggning av reparationsprocessen på Westermo Teleindustri AB: Identifiering av slöserier och förslag till förbättringar2014Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    This report is the result of a thesis performed at Westermo Industrial Ltd with its headquarters in Stora Sundby and it sums up the author's studies for University Engineering in Innovation, Production and Logistics at Mälardalen University.

    The main goal of the thesis was to identify problems and suggest actions that lead to the reduction of the repair time from 3 weeks to 2 weeks. The key questions that were answered in order to achieve the thesis objectives are:

     

    What are the biggest challenges that make the repair process time last for 3 weeks?

     

    What are the necessary means and measures in order to reduce the repair length to 2 weeks?

     

    The author adjusted the work to the Swedish repairs, repair issues that arise from sell unit Westermo Data Communications AB with its office in Västerås and performed the status report by mapping the repair process, through using observations, interviews and bibliography research studies. A flow map of four sub-processes (Inbound Delivery, BackOffice, Repair Department, and Logistics) was made and each section was observed, where also the employees were interviewed. Data that has been collected was analysed by the author and the decision to execute a workshop that affects Repair Department and Logistics was made. Consequently to this, these two services will prove to have the greatest impact on repair time.

     

    It is notified that the main reason for the repair process length today is so long is due to the fact that the owner of the repair process does not exist, which leads to so many unanswered questions and unclearness through the whole process, which occur and result in the situation where the process does not work as a whole, but each sub-process is acting separately on its own. Problems also arise because of the persons that are bound to the process, where both engineers at repair department are specialized in their own field and cannot perform the second engineer's work. Furthermore, due to the incomplete description that is usually provided by the customers, makes even more difficult to define the problem, which is yet another reason why the repair time is so long today.

     

    The suggestions for improvement that are recommended, in the first place to reduce the length of the repair process - is to create an entirely new position within repair process – the owner. In order to correct the deficiency with incomplete error descriptions from the clients, they should introduce network-based fault reports, which contain a number of mandatory fields that the customer must fill out in order to describe the problem and the conditions that existed when the fault with their unit occurred. This would simultaneously also eliminate the waiting length on the warranty of the unit if it is not applicable, and a response regarding that particular repair for the customer. Furthermore, training of repair engineers should be initiated for them, so they will be able to fix all units coming in for repair. The key objective here is to reduce the waiting length when the unit is on wait to be treated by the "right" engineer.

     

    In future, with the aforementioned, and other improvement proposals that are developed and explained in this report, repair time can be significantly reduced, which will further on improve the entire repair process.

    Fulltekst (pdf)
    divafulltext
  • 34.
    Morberg, Christin
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Öhlin, Sara
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Byggstenar för Husmuttern inför en ISO 9001-certifiering: Ett underlag för hur små och medelstora företag ska kunna påbörja en implementering av kvalitetsledningssystemet2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Denna studie är en slutlig undersökning av ett examensarbete som skrevs under hösten 2017 på Mälardalens högskola av två ingenjörsstudenter. Studien berör hur ett fallföretag i framtiden ska kunna genomföra en ISO-certifiering, vilket kommer att ge byggstenar till företaget för hur en implementering skulle kunna genomföras. Med hjälp av ISO-standardens sju grundprinciper – kundfokus, ledarskap, medarbetarnas engagemang, processinriktning, förbättring, faktabaserade beslut och relationshantering – ger det företaget en stabil grund att stå på, samt förutsättningar för att kunna införa ett kvalitetsledningssystem.

    Studien kommer att besvara problemformuleringen ”Att definiera glappet mellan ISO-standarden och fallföretaget.” Problemformulering är alldeles för övergripande för studiens tidsram och innefattar för stort arbete och har därför delats in i två mindre frågeställningar:

    1. Vilka utmaningar ställs små och medelstora företag, såsom Husmuttern, inför vid en implementering av ISO 9001?

    2. Hur kan små och medelstora företag hantera utmaningarna att bli ISO-certifierade?

    Informationen till studien har funnits med hjälp av en litteraturstudie och intervjuer för att få fram de byggstenar fallföretaget behöver inför deras framtida implementering. Litteraturstudien har bland annat bestått av artiklar, böcker och den internationella, officiella standarden ISO 9001:2015 för en ISO-certifiering. Intervjuerna har kvalitativt genomförts med semistrukturerade frågor tillsammans med fallföretagets VD, samt med VD:n på Mektig Technology Group. För att kunna genomföra studien användes en rekommenderad arbetsprocess på fyra steg från handboken ISO 9001 för små och medelstora företag (Bowin, 2002).

    Studiens teori har tillsammans med fallföretagets nulägesanalys sammanfattats i bland annat den fortsatta rekommendationen att fallföretaget ska påbörja en dokumentation av alla deras arbetsprocesser och policys inom företaget. Ytterligare rekommendationer består av att fallföretaget tar hjälp av extern hjälp, såsom utbildningar och kurser. Extra viktigt, som studien kommit fram till är att en implementering av en ISO-certifiering bör vara väl genomtänkt och planerat då det är både tidskrävande och kostsamt för ett företag att genomföra.

    En ISO-certifiering är väldigt tidskrävande och därför har endast denna studie kommit med underlag för hur fallföretaget skulle kunna genomföra en ISO-certifiering. Eftersom detta endast är ett underlag behöver fortsatta studier och rekommendationer, som nämnts ovan, genomföras.

    Fulltekst (pdf)
    fulltext
  • 35.
    Nidadavolu, Poonam
    Mälardalens universitet, Akademin för innovation, design och teknik.
    PREDICTIVE MAINTENANCE OF CENTRIFUGAL PUMPS USING REINFORCEMENT LEARNING2023Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Maintenance costs account for a significant portion of operation costs in manufacturing and production plants. An effective equipment maintenance strategy is crucial for ensuring reliable and safe operations and contributes to profitability by minimizing equipment downtime and reducing overall costs. Predictive maintenance has been a popular strategy for optimizing the operational planning of equipment. In contrast to traditional maintenance strategies, where maintenance actions are taken either at regular intervals or in a reactive manner after faults have occurred, predictive maintenance relies on condition monitoring to predict future equipment health and anticipate equipment failures before they occur. This strategy ensures that maintenance can be planned in advance, thereby curing operational downtime costs and improving process efficiency. This thesis introduces a model-free Reinforcement Learning (RL) based Predictive maintenance system for centrifugal pumps to identify any abnormal operating conditions of the pump and monitor processes to detect pump failures related to seal oil leakage. Based on the historical and real-time dataset, RL-based predictive maintenance systems learn optimal policies over time for identifying abnormal behaviour to plan maintenance, thus cutting operational downtime costs and improving process efficiency. An experiment was also conducted to compare the performance of predictive maintenance systems implemented using the RL-based approach with clustering and novelty detection approaches that employ Machine Learning (ML) and Deep Learning (DL) algorithms. Furthermore, the trained RL agent is applied to a pump with different distributions to check the model’s generalizability. The results show that the RL-based approach was able to create an effective predictive maintenance system with a lesser execution time and fewer training samples. The proposed approach showed the highest efficiency in performance compared to the Clustering and Novelty detection approaches. 

  • 36.
    Nåhdin, Rickard
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Arrestor Hook för JAS 39 Gripen2010Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    SAAB AB är intresserad av att kunna utrusta JAS 39 Gripen med en "Arrestor Hook" då denna typ av nödbromssystem är vanligare i andra flygvapen än det system som svenska flygvapnet använder. Uppgiften var att göra ett konstruktionsförslag av denna "Arrestor Hook" bom och krok för kommande arbete.

    För att göra detta förslag valdes att dela upp arbetet i fyra steg, faktainsamlig, konceptframtagande, konceptval och bearbetning.

    Valet av vilka detaljer som skulle ingå i förslaget var böjd bom med med fast krok. På kroken monterades en släpsko för att underlätta fångandet av vajern och att tjäna som den detalj som skyddar kroken från slitage som uppstår mellan "Arrestor Hook" och banbeläggning. För att tillgodose alla krav på rörlighet som behövs på "Arrestor Hook" utrustas den med en leddetalj som ger tvåfrihetsgrader vilket även ger ett mindre moment på konstruktionen när vajern är fångad.

    Resultatet av den teoretiska analysen av de fyra förslagen visar att alla de uppsatta kraven kan mötas, dock behövs mer utvärdering och tester för att säkerställa detta. Ytterligare litteratur kring tillvägagångssättet att konstruera "Arrestor Hook" bör också tillföras för fortsatt arbete.

    Fulltekst (pdf)
    FULLTEXT01
  • 37.
    Olsson, Erik
    Mälardalens universitet, Akademin för innovation, design och teknik.
    ERROR DETECTION IN PRODUCTION LINES VIA DEPENDABLE ARCHITECTURES IN CONVOLUTIONAL NEURAL NETWORKS2023Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The need for products has increased during the last few years, this high demand needs to bemet with higher means of production. The use of neural networks can be the key to increasedproduction without having to compromise product quality or human workers well being. This thesislooks into the concept of reliable architectures in convolutional neural networks and how they canbe implemented. The neural networks are trained to recognize the features in images to identifycertain objects, these recognition is then compared to other models to see which of them had the bestprediction. Using multiple models creates a reliable architecture from which results can be produced,these results can then be used in combinations with algorithms to improve prediction certainty. Theaim of implementing the networks with these algorithms are to improve the results without havingto change the networks configurations.

    Fulltekst (pdf)
    fulltext
  • 38. Pesämaa, Ossi
    et al.
    Hair, J.F.
    Klefsjö, Bengt
    Örtqvist, Daniel
    Luleå tekniska universitet, Innovation och Design.
    Developing a thermometer measuring tourist's needs, expectations and experiences: an empirical study of visitors in Norrbotten2007Rapport (Annet vitenskapelig)
  • 39.
    Pesämaa, Ossi
    et al.
    Luleå University of Technology, Sweden.
    Hair, Joseph F.
    Kennesaw State University, USA.
    Kvist, Anna-Karin
    When collaboration is difficult: the impact of dependencies and lack of suppliers on small and medium sized firms in a remote area2007Inngår i: World Journal of Tourism Small Business Management, ISSN 1991-1394, Vol. 1, s. 6-11Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To ensure their success, small and medium sized firms must collaborate. This study reports the perceptions of tourism firms in Eastern Norrbotten, Sweden regarding collaboration. The findings indicate a very low level of collaboration and a lack of understanding of the dependencies among tourism firms and the benefits of reciprocity.

  • 40.
    Rastegari, Ali
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Condition Based Maintenance in the Manufacturing Industry: From Strategy to Implementation2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The growth of global competition has led to remarkable changes in the way manufacturing companies operate. These changes have affected maintenance and made its role even more crucial for business success. To remain competitive, manufacturing companies must continuously increase the effectiveness and efficiency of their production processes. Furthermore, the introduction of lean manufacturing has increased concerns regarding equipment availability and, therefore, the demand for effective maintenance. That maintenance is becoming more important for the manufacturing industry is evident in current discussions on national industrialization agendas. Digitalization, the industrial internet of things (IoT) and their connections to sustainable production are identified as key enablers for increasing the number of jobs in industry. Agendas such as “Industry 4.0” in Germany and “Smart Industry” in Sweden are promoting the connection of physical items such as sensors, devices and enterprise assets, both to each other and to the internet. Machines, systems, manufactured parts and humans will be closely interlinked to collaborative actions. Every physical object will formulate a cyber-physical system (CPS), and it will constantly be linked to its digital fingerprint and to intensive connection with the surrounding CPSs of its on-going processes.

    That said, despite the increasing demand for reliable production equipment, few manufacturing companies pursue the development of strategic maintenance. Moreover, traditional maintenance strategies, such as corrective maintenance, are no longer sufficient to satisfy industrial needs, such as reducing failures and degradations of manufacturing systems to the greatest possible extent. The concept of maintenance has evolved over the last few decades from a corrective approach (maintenance actions after a failure) to a preventive approach (maintenance actions to prevent the failure). Strategies and concepts such as condition based maintenance (CBM) have thus evolved to support this ideal outcome. CBM is a set of maintenance actions based on the real-time or near real-time assessment of equipment conditions, which is obtained from embedded sensors and/or external tests and measurements, taken by portable equipment and/or subjective condition monitoring. CBM is increasingly recognized as the most efficient strategy for performing maintenance in a wide variety of industries. However, the practical implementation of advanced maintenance technologies, such as CBM, is relatively limited in the manufacturing industry.

    Based on the discussion above, the objective of this research is to provide frameworks and guidelines to support the development and implementation of condition based maintenance in manufacturing companies.  This thesis will begin with an overall analysis of maintenance management to identify factors needed to strategically manage production maintenance. It will continue with a focus on CBM to illustrate how CBM could be valued in manufacturing companies and what the influencing factors to implement CBM are. The data were collected through case studies, mainly at one major automotive manufacturing site in Sweden. The bulk of the data was collected during a pilot CBM implementation project. Following the findings from these efforts, a formulated maintenance strategy is developed and presented, and factors to evaluate CBM cost effectiveness are assessed. These factors indicate the benefits of CBM, mostly with regard to reducing the probability of experiencing maximal damage to production equipment and reducing production losses, particularly at high production volumes. Furthermore, a process of CBM implementation is presented. Some of the main elements in the process are the selection of the components to be monitored, the techniques and technologies for condition monitoring and their installation and, finally, the analysis of the results of condition monitoring. Furthermore, CBM of machine tools is presented and discussed in this thesis, focusing on the use of vibration monitoring technique to monitor the condition of machine tool spindle units.

    Fulltekst (pdf)
    fulltext
  • 41.
    Rastegari, Ali
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Strategic Maintenance Development focusing on use of Condition Based Maintenance in Manufacturing Industry2015Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The growth of global competition caused remarkable changes in the way manufacturing companies operate. These changes have affected maintenance and made its role even more crucial in business success. In order to stay competitive, manufacturing companies need to continuously increase the effectiveness and efficiency of their production processes. Further, by introducing lean manufacturing the concern about equipment availability is increased and so, the demand for effective maintenance. Despite the increasing demand on reliable production equipment, few manufacturing companies work with strategic maintenance development. Moreover, conventional maintenance strategies such as corrective maintenance are not sufficient today to fulfill the industrial needs on maximum reduction of failures and degradations of manufacturing systems. The concept of maintenance has evolved over the last few decades from a corrective attitude (maintenance intervention after a failure), to a predictive attitude (maintenance intervention fixed to prevent the fault). Strategies and concepts such as Condition Based Maintenance (CBM) have thus evolved to support this ideal situation. CBM is a set of maintenance actions based on real-time or near real-time assessment of equipment condition, which is obtained from embedded sensors and/or external tests and measurements taken by portable equipment and/or subjective condition monitoring. CBM is becoming recognized as the most efficient strategy for carrying out maintenance in a wide variety of industries. However, the practical implementation of advanced maintenance technologies, such as CBM, in manufacturing industry is more scarce.

    Therefore, the objective with this research is to study on how to implement and develop an effective and efficient CBM strategy in manufacturing industry. This thesis will start with an analysis of the overall maintenance management to illustrate how to formulate a maintenance strategy, following with the focus on CBM; cost effectiveness of implementing CBM; an introductory review of applied CBM practices and CBM implementation process, all in manufacturing industry. The data was collected through case studies mainly at one major manufacturing site. The main part of the data was collected during a pilot project to implement CBM. As the result, a formulated maintenance strategy has been developed and presented. Factors to evaluate CBM cost effectiveness have been assessed. These factors indicate the benefits of CBM mostly in reducing probability of having maximal damage in production equipment and reducing production losses particularly in high production volumes. Further, a process of CBM implementation has been presented. Some of the main elements in the process are selection of the components to be monitored, techniques and technologies as well as installation of the technologies and finally how to analyze the results from the condition monitoring.

    Fulltekst (pdf)
    fulltext
  • 42.
    Rastegari, Ali
    et al.
    Volvo Group Trucks Oper. Powertrain Production, Köping, Sweden.
    Bengtsson, Marcus
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Cost Effectiveness of Condition Based Maintenance in Manufacturing2015Inngår i: Reliability and Maintainability Symposium, IEEE conference proceedings, 2015, artikkel-id Article number 7105079Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents a proposed guide for analysis of the costs and benefits of implementing Condition Based Maintenance (CBM) in manufacturing industry. The guide will be exemplified with results from a case study performed in a real CBM implementation in hardening and machining processes in a large manufacturing facility. The result indicates factors that ought to be taken into consideration in order to evaluate both the cost of implementing CBM and its benefits. These factors indicate the benefits of CBM mostly by reducing the losses due to damage in the production equipment, including capital loss, production loss, quality loss, environmental loss, safety loss etc. By analyzing the empirical data, the most potential savings by implementing CBM are presented as; reducing the probability of having maximal damage in the production equipment and, reducing production losses particularly in high production volumes.

  • 43.
    Rastegari, Ali
    et al.
    Volvo GTO, Köping, Sweden .
    Bengtsson, Marcus
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Implementation of Condition Based Maintenance in Manufacturing Industry – A Pilot Case Study2014Inngår i: 2014 IEEE Conference on Prognostics and Health Management (PHM), IEEE conference proceedings, 2014, s. Article number 7036377-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents a guide for implementation of Condition Based Maintenance (CBM) in a manufacturing industry, considering the technical constituents and organizational aspects when implementing CBM. The empirical base for the study is a case study from a major manufacturing site in Sweden. The data was collected during a pilot project to implement CBM at the case company. The purpose of the pilot study at the company was to implement online condition monitoring on some of the critical components in the hardening process. Hereby, two of the main online condition monitoring techniques namely vibration analysis and Shock Pulse Method (SPM) have been implemented and tested on electric motors to monitor bearing conditions. The paper presents the process of implementation and the elements included in this process. Some of the main elements in the implementation process are selection of the components to be monitored, techniques and technologies as well as installation of the technologies and finally how to analyze the results from the condition monitoring. The data from online condition monitoring on the electric motors, driving the furnace fans, are recorded and presented in the paper including breakdown data on two objects. This information is leading to useful and reliable knowledge for maintenance work to be cost effective and be able to increase the overall equipment availability (OEA). In addition to this, the result indicates to what extent advanced CBM practices are applicable in the hardening environment in the manufacturing company and it provides guidance for further research and development in this area. The paper concludes with a discussion on possible future trends and research areas, needed to increase the effective and efficient use of CBM.

  • 44.
    Rastegari, Ali
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering. Volvo GTO, Köping, Sweden.
    Salonen, Antti
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering. Volvo GTO, Köping, Sweden.
    Strategic maintenance management: Formulating maintenance strategy2015Inngår i: International Journal of COMADEM, ISSN 1363-7681, Vol. 18, nr 1, s. 5-14Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In recent decades, by introducing lean manufacturing the vulnerability to system disturbances has increased and so, the demand for dependable production equipment. The need for having high production equipment availability causes companies to need a more effective and efficient maintenance strategy in order to stay competitive. Despite the increasing demand on reliable production equipment, few manufacturing companies work with strategic maintenance development and a large part of the manufacturing industry lack clear maintenance strategies. It is therefore difficult to develop the maintenance work in accordance with the strategic goals of the manufacturing companies.

    The main objective of this paper is to define a process for formulating maintenance strategy in order to facilitate further development in a strategic way. The problem has been studied by literature review and through case study at one major manufacturing site in Sweden to investigate the company’s view on strategic maintenance development. Hence, a formulated maintenance strategy has been provided and presented. The company’s overall goals considered and translated to the strategic objective of maintenance. Moreover, balanced score card is used as a tool to make a framework of the maintenance strategy. As a result of this study, the company could easily formulate a maintenance strategy by using a simple process based on the tools that they have already used. In addition to this, the result indicated how maintenance strategy can contribute to the company’s business goals.

  • 45.
    Röstlund, Jessica
    Mälardalens högskola, Institutionen för innovation, design och produktutveckling.
    Miljöutredning för Elisolation HTM AB2007Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Denna miljöutredning avser företaget Elisolation htm AB, som ingår i Söderberg företagen och är

    lokaliserat i Laxå, Närke. Företaget bedriver försäljning, tillverkning och lagerhållning av

    härdplaster och termoplaster med goda elektriska, mekaniska och temperaturegenskaper.

    Idag är ISO 14001 ett konkurrensmedel som inget företag kan bortse från. Allt fler företag

    arbetar enligt miljösystemet och ställer därför krav på att även deras samarbetspartners och

    underleverantörer gör det. Klarar du inte av att möta dina kunders krav så finns risken att de

    vänder sig till en konkurrent.

    Detta examensarbete är en miljöutredning som är en del av miljöarbete på Elisolation htm AB

    och utredningen är det första och grundläggande steget i processen med att införa ISO 14001 i

    verksamheten. Motivet med en miljöutredning är att ge en nulägesbeskrivning av Elisolation htm

    AB:s aktiviteter, verksamheter och tjänster som påverkar miljön mest och att identifiera de

    miljöaspekter som finns på företaget.

    Fulltekst (pdf)
    FULLTEXT01
  • 46.
    Sahlander, Roland
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Framtagande av dynamiskt VSM-verktyg: Ett utvecklingsarbete hos ABB Robotics2017Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    ABSTRACT

    Introduction and purpose

    Development of a VSM tool has been done by performing experimental field work at ABB Robotics, a company that mass produces industrial robots and associated accessories. The tool development, the primary part of the project, mainly puts focus on production aspects. Furthermore, it has been centered on plant layouts of the product layout kind (production line).

    The purpose of the development is to create a tailored VSM tool that auto generates a foundation for value stream maps based on calculations and possibly simple simulation. The purpose is broken down into two questions where concrete problems can be illustrated:

    A) How should the VSM tool plainly signal capacity vs. demand, time balances in production and the ratio between value and non-value adding aspects as well as intuitively promote knowledge and in a simple and fast manner be applicable to different kinds of production lines?

    B) Which constraints are placed on the potential of the VSM tool due to the current situation of the company, how does this contradict the main principles of VSM and how can the company work to maximize the tool´s potential in the future?

    Methodology and knowledge

    The development which is characterized by continuous counseling and feedback with the internal mentor is mainly based on laboratory work in Excel. In addition, the work has also involved the making of a user guide as well as an adjustable function for indicating production effects with colors. An evaluation of the tool and the user guide has also been made, which mainly is supported by a test run with the internal mentor and the nature of the methodology.

    The knowledge that the development uses as its footing mainly involves process- and value stream maps from the company, discussions with company personnel, self-performed laboratory work and theory from Rother and Shooks book “Lära sig se” (2005) and Drew. A. Locher´s book “Value Stream Mapping for Lean Development” (2008).

    Results

    The VSM tool manages, in a relevant way, to factor in all aspects that can be interpreted using a typical value stream map. In addition it also provides the following: balances between workstations and production lines, suggestions for amount of WIP between these, simple simulation of WIP between these, disturbance aspects, three total times; manufacturing lead time, inventory time and value adding time as well as a graphic illustration over production courses. The results are considered to fulfill the purpose of the project.

    Conclusion and future meaning

    The development results in a hybrid solution of sorts, a tool that exists somewhere in-between the typical draw-by-hand VSM work and simulation software. Its advantage is that it combines VSM theory with intuitive, swift and practical usage, which goes well in hand with today´s fluctuating conditions where time pressure of different kinds are present. The drawback is that the concept as a whole requires complementing in the form of Lean knowledge and gemba observations. Furthermore, there are implications associated with some types of parallel production and editing of the tool, which is to be addressed before implementation. In order to fully utilize the tool, the company also has to examine production times and make a minor adjustment to the process of collecting disturbance data. Three suggestions for the future are given; to study availability, transport aspects and the measuring of production times.

    Fulltekst (pdf)
    fulltext
  • 47.
    Saleh, Wisam
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    El Elawi, Muhamad
    Processer för hantering av luftfartyg eller komponenter efter händelse:  2012Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Fulltekst (pdf)
    Processer för hantering av luftfartyg eller komponenter efter händelse
  • 48.
    Salonen, Antti
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Human errors in Industry 4.0: Opportunities and challenges from a dependability perspective2019Inngår i: Proceedings of 4th International Conference on Maintenance Engineering, Manchester, 2019, s. 69-78Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In manufacturing industry, more than 20% of the breakdowns are caused by human errors, either by operators or by the maintenance staff. With the introduction of new ICT, the industry 4.0 may very well help reducing some of these errors, but may very well introduce new causes of human errors as well. This paper discusses some of the opportunities and challenges that the industry 4.0, may arise in the human error aspect of dependability in discrete manufacturing systems.

  • 49.
    Salonen, Antti
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Gopalakrishnan, Maheshwaran
    Chalmers Tekniska Högskola, Goteborg.
    Practices of preventive maintenance planningin discrete manufacturing industry2021Inngår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 27, nr 2, s. 331-350Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    "Purpose – The purpose of this study was to assess the readiness of the Swedish manufacturing industry to implement dynamic, data-driven preventive maintenance (PM) by identifying the gap between the state of the art and the state of practice.

    Design/methodology/approach – An embedded multiple case study was performed in which some of the largest companies in the discrete manufacturing industry, that is, mechanical engineering, were surveyed regarding the design of their PM programmes.

    Findings – The studied manufacturing companies make limited use of the existing scientific state of the art when designing their PM programmes. They seem to be aware of the possibilities for improvement, but they also see obstacles to changing their practices according to future requirements.

    Practical implications – The results of this study will benefit both industry professionals and academicians, setting the initial stage for the development of data-driven, diversified and dynamic PM programmes.

    Originality/Value – First and foremost, this study maps the current state and practice in PM planning among some of the larger automotive manufacturing industries in Sweden. This work reveals a gap between the stateof the art and the state of practice in the design of PM programmes. Insights regarding this gap show large improvement potentials which may prove important for academics as well as practitioners."

  • 50.
    Sankaranarayanan, Vairamayil
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Maintenance – Wind Energy Production2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This thesis investigates issues like maintenance problems, key factors, maintenance challenges, maintenance solutions and practical difficulties in wind energy. In this case, surveys and interviews have been taken from several companies and maintenance experts, to find most prevailing problems and problem-solving methods since last few years. It helps to show, how the energy maintenance has been developed in past few years. Also it analyses the impact of fourth generation maintenance in wind energy production. From research questions, key factors involved in wind energy maintenance provides us with valuable suggestions to develop the maintenance methods in future vision.

    Fulltekst (pdf)
    fulltext
12 1 - 50 of 53
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