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  • 1.
    Abbas, Nada
    et al.
    Linnaeus University, Faculty of Technology, Department of Informatics.
    Kans, Mirka
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering. Chalmers University of Technology, Sweden.
    Information Needs of Gravel Road Stakeholders2022In: Infrastructures, E-ISSN 2412-3811, Vol. 7, no 12, article id 166Article in journal (Refereed)
    Abstract [en]

    Within any ecosystem, information sharing is essential. In this paper, the Swedish gravel road ecosystem is studied, where information plays a crucial role for the effective management of operations and maintenance. However, efficient information sharing is not enabled due to the lack of appropriate information systems. For addressing this issue, this paper intends to elicit information needs of gravel road stakeholders to support the design of a cloud-based information system. The main purpose is to explore the information needs of stakeholders within the Swedish gravel road ecosystem. Data were collected through in-depth semi-structured interviews with 11 participants representing key stakeholders in the ecosystem. Template analysis was used for analyzing the interview results. The major findings were a set of information needs covering road identification and condition, weather conditions, accessibility and traffic, maintenance policy, and sensor data. The results form a comprehensive information model for the further development of a cloud-based gravel road management system that would contribute to increased traffic safety and comfort, lower maintenance and management costs, and better decision-making abilities.

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  • 2.
    Abdi, Adna Adam
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Demirovic, Adis
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    A concept development of the HirePadlock product.: With a focus on setting requirements for the product and implementing a customer survey2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Many industrial companies place high demands on product development, from a simple idea to a finished product and then bring it to market. Therefore, there has been a rapid development of methods, models and working methodes in product development. This development is mostley about the product having a balance between price, quality, customer adaptation, safety, production and less environmental impact. 

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  • 3.
    Abelen, Aisha
    et al.
    Eindhoven Univ Technol, Netherlands.
    Kroon, Martin
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Modelling of rate-dependent inelasticity and damage in semi-crystalline polymers using an Eulerian framework2023In: International Journal of Engineering Science, ISSN 0020-7225, E-ISSN 1879-2197, Vol. 193, article id 103945Article in journal (Refereed)
    Abstract [en]

    The present paper concerns the mechanical response of semi-crystalline polymers during cyclic loading, and it includes both modelling and experimental testing. The model is Eulerian in the sense that it is independent of measures of total deformation and plastic/inelastic deformations. It is able to account for such essential phenomena as strain-rate dependence, work hardening, and damage. The model was applied to uniaxial tension tests performed on high-density polyethylene (HDPE), which is a semi-crystalline polymer widely used in the industry. Two types of tests were conducted: monotonic tests, and loading-unloading tests. The model was able to reproduce the experimental results very well. The proposed model was also implemented as a UMAT in Abaqus, including an analytic tangent. The UMAT was used for simulating two 3D geometries. The implementation seems to be robust, and no convergence problems were observed.

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  • 4.
    Ablay, Talip
    Linnaeus University, Faculty of Engineering and Technology, Department of Mechanical Engineering.
    Maintenance Perception in Swedish SMEs (A local study in Kronoberg County)  2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Recognition of maintenance management as a significant factor holds the key to competitiveness in the global market irrespective of the size of the business. Maintenance management practices are primarily found in larger and multinational companies but the purpose of this paper is to investigate the maintenance practices that are used in SMEs of Sweden (Kronoberg County). The study is expected to expose the level of maintenance perception in the Swedish industry via a postal (and web based) questionnaire. The survey covered 74 company chosen from different sectors and produced a response rate of 20.3 percent. The main results achieved from the study show us difference between the maintenance perception and awareness of the maintenance. The respondents are aware of the importance of maintenance, but maintenance is still perceived as a necessary expense. Because according to the results of the survey the percentage of maintenance budget in comparison to the companies’ turnover is on average about 0.97% and it is very low. Again, when we look at the maintenance cost distribution of companies, spare parts and labour costs consist of 73 % of total maintenance cost, despite that they spend very little money for technology and training costs, their percentages in total cost are just 3% and 2%, also they still ignore statistical modelling (historical data) and condition monitoring. Moreover, just 27% of the participants use the maintenance key performance indicators (KPIs), and just 14% of them used basic KPIs which are used for measuring maintenance performance. There is a need to spend and invest more in maintenance especially they should invest more in technology and training to perform them. On the other hand, there is a need for choosing right maintenance strategy and service type, because these points are very important for an effective and economic maintenance management.

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  • 5.
    Abrahamsen, Rune
    et al.
    Moelven Limtre, Norway.
    Bjertnaes, Magne A.
    Sweco, Norway.
    Bouillot, Jacques
    Eiffage, France.
    Brank, Bostjan
    University of Ljubljana, Slovenia.
    Cabaton, Lionel
    Arbonis, France.
    Crocetti, Roberto
    Moelven, Sweden.
    Flamand, Olivier
    CSTB, France.
    Garains, Fabien
    Eiffage, France.
    Gavric, Igor
    InnoRenew, Slovenia.
    Germain, Olivier
    Galeo, France.
    Hahusseau, Ludwig
    Eiffage, France.
    Hameury, Stephane
    CSTB, France.
    Johansson, Marie
    RISE, Sweden.
    Johansson, Thomas
    Moelven, Sweden.
    Ao, Wai Kei
    University of Exeter, UK.
    Kurent, Blaz
    University of Ljubljana, Slovenia.
    Landel, Pierre
    RISE, Sweden.
    Linderholt, Andreas
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Malo, Kjell
    NTNU Norwegian University of Science and Technology, Norway.
    Manthey, Manuel
    CSTB, France.
    Nåvik, Petter
    Sweco, Norway.
    Pavic, Alex
    University of Exeter, UK.
    Perez, Fernando
    Smith and Wallwork, UK.
    Rönnquist, Anders
    NTNU Norwegian University of Science and Technology, Norway.
    Stamatopoulos, Haris
    NTNU Norwegian University of Science and Technology, Norway.
    Sustersic, Iztok
    InnoRenew, Slovenia.
    Tulebekova, Salue
    NTNU Norwegian University of Science and Technology, Norway.
    Dynamic Response of Tall Timber Buildings Under Service Load: The DynaTTB Research Program2020In: EURODYN 2020, XI international conferece on structural dynamics: Proceedings, Volym II / [ed] M. Papadrakakis, M. Fragiadakis, C. Papadimitriou, National Technical University of Athens , 2020, p. 4900-4910Conference paper (Refereed)
    Abstract [en]

    Wind-induced dynamic excitation is becoming a governing design action determin-ing size and shape of modern Tall Timber Buildings (TTBs). The wind actions generate dynamic loading, causing discomfort or annoyance for occupants due to the perceived horizontal sway – i.e. vibration serviceability failure. Although some TTBs have been instrumented and meas-ured to estimate their key dynamic properties (natural frequencies and damping), no systematic evaluation of dynamic performance pertinent to wind loading has been performed for the new and evolving construction technology used in TTBs. The DynaTTB project, funded by the Forest Value research program, mixes on site measurements on existing buildings excited by heavy shakers, for identification of the structural system, with laboratory identification of building elements mechanical features coupled with numerical modelling of timber structures. The goal is to identify and quantify the causes of vibration energy dissipation in modern TTBs and pro-vide key elements to FE modelers.

    The first building, from a list of 8, was modelled and tested at full scale in December 2019. Some results are presented in this paper. Four other buildings will be modelled and tested in spring 2020.

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  • 6.
    Abrahamsen, Rune
    et al.
    Moelven Limtre, Norway.
    Bjertnæs, Magne A.
    Sweco, Norway.
    Bouillot, Jacques
    Eiffage, France.
    Brank, Boštjan
    University of Ljubljana, Slovenia.
    Crocetti, Roberto
    Moelven SE, Sweden.
    Flamand, Olivier
    CSTB, France.
    Garains, Fabien
    Arbonis, France.
    Gavrić, Igor
    InnoRenew, Slovenia.
    Hahusseau, Ludwig
    Eiffage, France.
    Jalil, Alan
    CSTB, France.
    Johansson, Marie
    RISE, Sweden.
    Johansson, Thomas
    Moelven, Sweden.
    Ao, Wai Kei
    Uni Exeter, UK.
    Kurent, Blaž
    University of Ljubljana, Slovenia.
    Landel, Pierre
    Linnaeus University, Faculty of Technology, Department of Building Technology. Rise, Sweden.
    Linderholt, Andreas
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Malo, Kjell
    NTNU, Norway.
    Manthey, Manuel
    CSTB, France.
    Nåvik, Petter
    Sweco, Norway.
    Pavic, Alex
    Uni Exeter, UK.
    Perez, Fernando
    Smith&Wallwork, Switzerland.
    Rönnquist, Anders
    NTNU, Norway.
    Šušteršič, Iztok
    InnoRenew, Slovenia.
    Tulebekova, Saule
    NTNU, Norway.
    Dynamic response of tall timber buildings under service load: results from the dynattb research program2023In: World Conference on Timber Engineering 2023 (WCTE 2023): Timber for a Livable Future, 19-22 june, 2023,Oslo, Norway / [ed] Nyrud, A. Q. and Malo, K. A. et al., Curran Associates, Inc., 2023, p. 2907-2914Conference paper (Refereed)
    Abstract [en]

    Wind-induced dynamic excitation is a governing design action determining size and shape of modern Tall Timber Buildings (TTBs). The wind actions generate dynamic loading, causing discomfort or annoyance for occupants due to the perceived horizontal sway, i.e. vibration serviceability problem. Although some TTBs have been instrumented and measured to estimate their key dynamic properties (eigenfrequencies, mode shapes and damping), no systematic evaluation of dynamic performance pertinent to wind loading had been performed for the new and evolving construction technologies used in TTBs. The DynaTTB project, funded by the ForestValue research program, mixed on site measurements on existing buildings excited by mass inertia shakers (forced vibration) and/or the wind loads (ambient vibration), for identification of the structural system, with laboratory identification of building elements mechanical features, coupled with numerical modelling of timber structures. The goal is to identify and quantify the causes of vibration energy dissipation in modern TTBs and provide key elements to finite element models. This paper presents an overview of the results of the project and the proposed Guidelines for design of TTBs in relation to their dynamic properties.

  • 7.
    Abrahamsson, Max
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Persson, Ludwig
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Vidareutveckling av en låsmekanism för att minska bullernivån på en dumper2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med arbetet är att undersöka hur bullernivån kan minskas eller elimineras genom att utveckla en lösning som förhindrar bakluckan på Volvos A45 dumper från att studsa. Genom en utvecklad och noggrann produktutvecklingsprocess redovisades 14 olika koncept. Tillsammans med Volvo CE valdes ett koncept som var en vidareutveckling från en tidigare lösning. Resultatet är en robust och funktionssäker lösning som minskar bullernivån samtidigt som det inte påverkar hållfastheten på dumpern negativt.

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  • 8.
    Abu Daqqa, Nizar
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Alan, Serkan
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    On the Requirements to Implement E-maintenance Cost effectively: Survey Study2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays, companies started to realize the impact of a good maintenance strategy on the production process. Quality, performance as well as availability are affected by maintenance; existing maintenance strategies help to optimize the production process to achieve high quality products with a low production cost. A new strategy of maintenance has immerged recently, e-maintenance provides an easy solution to follow up with maintenance, it provides condition monitoring, documentation, and it also gives you the best maintenance solution that fits your goals and vision. Articles related to e-maintenance was studied and analyzed to know the steps to implement a cost-effective e-maintenance. The authors came up with a model that describes the implementation process in three main steps.

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  • 9.
    Aggerstam, Elina
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Lehman, Karolina
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Materialvalets miljöpåverkan på transporten: En jämförelsestudie mellan transporter till flerfamiljshus i trä och betong.2017Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Under året 2015 bedömde 240 av Sveriges 290 kommuner att det existerade ett underslott på bostäder. För att kunna möta behovet krävs det att många bostäder ska byggas på en kort tid. Med de klimathot som världen står inför krävs det att produktionen är uthållig och hållbar i längden. För att nå klimatmålen måste användandet av tunga fordon minskas, logistiken måste effektiviseras och alternativa transportmedel bör undersökas.

    Syftet med studien var att identifiera eventuella skillnader mellan byggnadsmaterialen trä och betong i transportledet. Med den insamalade datan togs olika relations- och nyckeltal fram som sedan utgjorde basen för de två formlerna som presenteras i studien.

    Resultatet av de olika relationstalen indikerar på att den lastade vikten inte har stor betydelse på hur mycket CO2 som släpps ut, utan att det är antalet transporter med tung lastbil som är grundproblemet till utsläppen och miljöpåverkan. Med formlerna som presenteras i studien kan antalet transporter som krävs till ett flerfamiljshus räknas ut, men även mängden CO2 som släpps ut vid fraktandet av planelementen.

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    Materialvalets miljöpåverkan på transporten
  • 10.
    Ahl, Victor
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Klasén, Erik
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Evaluering av diskret händelsesimulering för produktionssystem: En jämförelsestudie av FACTS Analyzer och Plant Simulation i undervisande sammanhang2024Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of simulation programs in production environments is crucial due to the many advantages they offer, such as facilitating calculations of production capacity, cycle times, and optimal buffer sizes. These tools allow for the simulation of various scenarios and cost-effective testing of different strategies, making them invaluable for companies striving to improve production and performance. 

    The purpose of this work is to conduct a case study using FACTS Analyzer and then compare the results with another simulation software that supports 3D simulations. By conducting the same case study in both programs, we can draw conclusions about the factors companies should consider when acquiring simulation software. The data will be collected through qualitative methods such as observations and interviews, complemented by quantitative methods through experiments within the case study.

    The results show that FACTS Analyzer and the chosen program Plant Simulation serve different purposes but within similar areas. FACTS Analyzer offers a simple and effective 2D simulation experience that is particularly useful for students and companies planning production. On the other hand, Plant Simulation provides extensive capabilities to model everything from individual production lines to entire facilities in a clear 3D environment, making it easier for people without in-depth knowledge of the field to understand the simulations.

    In conclusion, the study shows that both programs can complement each other by offering unique capabilities in different domains, providing companies with a competitive advantage by optimizing their production and planning processes.

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  • 11.
    Ahlqvist, Carl
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Meijer, Niklas
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Identifiering av faktorer som kan påverka produktionseffektivitet: En fallstudie2015Independent thesis Basic level (university diploma), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Manufacturing industries are today facing increasing competition through the globalization of the market that takes place. A global market with several competitors, increased product differentiation and the high cost of production makes great demands on companies to work cost effectively. To be competitive and operate a profitable production requires companies to have a great knowledge of how their manufacturing processes work, has a high reliability and can use their facility's capacity.

     

    The basis for the study is the industrial profitability problems in Sweden, where companies find it increasingly difficult to produce quality products at a competitive price. The case study performed in a company which manufactures components for the automotive industry, with the aim to create a better understanding of the factors that lead to production disruptions and has great effect on the production efficiency of a flow. In order to be able to counter them and exploit the capacity of a better way and create a high level of competitiveness and profitability.

     

    Based on the analytical study and first described the present situation of the case now. This is followed by an analysis of the current situation where empiricism is compared with the relevant theory. The analysis then reports the measured values ​​of the factors that lead to disturbances in the production flow and affect production efficiency. Finally, the evaluation factors and an explanation of what they are due to be clarified. It results that the case study demonstrates the significant factors affecting production efficiency, as well as the underlying causes of these should be tackled in order to create a higher level of reliability and production efficiency in the flow. Examination of factors and causes creates a basis for the improvements that should be applied to maintain profitable production and competitiveness.

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  • 12.
    Ahmed, Sheikh Ali
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Adamopoulos, Stergios
    Swedish university of agricultural sciences, Sweden.
    Li, Junqiu
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kovacikova, Janka
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Prediction of mechanical performance of acetylated MDF at different humid conditions2020In: Applied Sciences, E-ISSN 2076-3417, Vol. 10, no 23, p. 1-16, article id 8712Article in journal (Refereed)
    Abstract [en]

    Change of relative humidity (RH) in surrounding environment can greatly affect the physical and mechanical properties of wood-based panels. Commercially produced acetylated medium density fiberboard (MDF), Medite Tricoya®, was used in this study to predict strength and stiffness under varying humid conditions by separating samples in parallel (//) and perpendicular (⊥) to the sanding directions. Thickness swelling, static moduli of elasticity (MOEstat) and rupture (MORstat), and internal bond (IB) strength were measured at three different humid conditions, i.e., dry (35% RH), standard (65% RH) and wet (85% RH). Internal bond (IB) strength was also measured after accelerated aging test. A resonance method was used to determine dynamic modulus of elasticity (MOEdyn) at the aforementioned humid conditions. Linear regression and finite element (FE) analyses were used to predict the MDF’s static bending behavior. Results showed that dimensional stability, MOEstat, MORstat and IB strength decreased significantly with an increase in RH. No reduction of IB strength was observed after 426 h of accelerated aging test. A multiple regression model was established using MOEdyn and RH values to predict MOEstat and MORstat. In both directions (// and ⊥), highly significant relationships were observed. The predicted and the measured values of MOEstat and MORstat were satisfactorily related to each other, which indicated that the developed model can be effectively used for evaluating the strength and stiffness of Medite Tricoya® MDF samples at any humid condition. Percent errors of two different simulation techniques (standard and extended FE method) showed highly efficient way of simulating the MDF structures with low fidelity.

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  • 13.
    Ahmetovic, Dario
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Capri, Mirlind
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Hållfasthetsanalys av draglåda för tillverkning av betongslipers för järnvägar2018Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Betongslipers är ett element i den moderna järnvägens uppbyggnad. Det har ersatt det traditionella virkesmaterialet som har ett antal nackdelar gentemot betong. Vid tillverkning av betongslipers förspänns armeringslinor med en kraft på 500 kN innan cementet gjuts in i produktionslinans formar. Undersökningen kommer in i bilden då en svetsad draglåda, där armeringslinorna är låsta, belastas av förspänningskraften. Uppdraget blir att analysera spänningsflödet i draglådan för att se var de största spänningarna förekommer. Detta görs genom en FEM-analys av hela konstruktionen samt hållfasthetsberäkningar av enbart gängorna.

    Slutsatsen som fastställdes var att analysen av konstruktionen resulterade att förspänningskraften inte påverkade gängorna eller svetsarna så pass kritisk att en allvarlig deformation skulle ske.

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  • 14.
    Al Kaysee, Ahmed
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Wronski, Marek
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Dynamic Substructuring of an A600 Wind Turbine2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A

    limited and extendable master thesis is representing the first step in the experimental substructuring of an A600 wind turbine. Additional masses have been designed, manufactured and added to the sub components for the laboratory experimental tests. Further preparations for dynamic experimental tests have been described and implemented. Vibrational tests of a modified wind turbine blade have been made using the Leuven Measurements System (LMS) for excitations and data acquisition purposes. The theory of frequency response function based substructuring applied on the wind turbine blade model is demonstrated. The theory and an example of a Matlab coded spring-mass system, an experimental model of a wind turbine blade and FRFs stemming from measurements are reported.

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  • 15.
    Alagbada, Adefemi Samuel
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Thermo-Mechanical Fatigue Assessment of Marine Boiler: Using linear Finite Element Analyses2020Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is on fatigue crack growth assessments of a thermomechanical loaded Marine Boiler- Sunrod CPDB12. The installation position of the marine boiler in the ship in relation to its fatigue life under mode 1 loading is investigated. Thermomechanical loading embodies pressures, temperatures, RAO, subjected to the rigid body dynamic of ship in the marine environment.

     

    Linear elastic fracture mechanics (LEFM) method was used is predicting the growth rates of the welding flaws at the joint based on stress range of the Paris law relationship. FEA Numerical simulation delivered better crack growth rate assessments and life predictions of the smallest detectable flaws in the boiler.

     

    The identified smallest detestable flaws at the welding joint diminishing the designed safe life of the boiler significantly.  Also, installation position within the ship do affect the fatigue life of the boiler.

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  • 16.
    Alazzawi, Muntaha
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Trust in Customer–Supplier relationships2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The competitive market of today is characterized by globalization, because of that organizations increased demands from customers on the services as well as on product. In other word, the customer is focusing on buying the service in same way as they buy products. For that the trust in relationships is considered as an important and effective factor when the business to business partners want to achieve growth profitability, and long term time. In order to reach high trust in relationships between customers and suppliers, ability to measure trust in relationships and to improve it is important. One to know how to be able to follow up the trust in the relationships between customers and suppliers, maintain and develop relationships for as long as possible in order to reach the company's goals. The first step in the project was data collection via an email survey and by direct contact with those companies by phone. Then the data was used to make an analysis by comports the results with pervious theories. The analysis enabled to identify the different types of factors which makes the trust in relationships more strong and stable .In the last chapters results are discussed and it was found that the each company has its own way to follow up the relationships to maintain the trust in relationships for longer  time to a achieve their goals and profit. The conclusions are each company have different way of measuring and regardless of which indicators are used for measuring the trust in relationships between the customer and service supplier, they must be  linked directly to the organization's  goals to maintain and  continuity relationships for as long as possible in order to reach the company's goals. The effective trust is important factor which lead to the partners feeling they belong to each other’s which the relationships between them  take a partner form which lead to long term time and profitable relationships and strong trust in relationships.

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  • 17.
    Al-Darwash, Mustafa
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Nuss, Emanuel
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Mechanical characterization of DuraPulp by means of micromechanical modelling2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Södra DuraPulp is a relatively new eco-composite, made from natural wood fibers and polylactic acid (PLA), which comes from corn starch. Until now, there are only few applications for DuraPulp, mainly in the area of design. To find new fields of application, more knowledge about its mechanical material properties are of great interest.This study deals with characterizing the mechanical properties of DuraPulp in an analytical way by means of micromechanical modelling and evaluation with help of Matlab. The mechanical properties for PLA were taken from scientific literature. Not all properties of the wood fibers could be found in literature (particularly Poisson’s ratios were unavailable). Therefore, they partly had to be assumed within reasonable boundaries. These assumptions are later validated regarding their influence on the final product.Figures and tables were used to present and compare the in- and out-of-plane E-Moduli, shear moduli and Poisson’s ratios of DuraPulp. The calculated in-plane E-Moduli were then compared to those obtained from an earlier study, where DuraPulp was tested in tension. The results showed that experimental and analytical values are very similar to each other.

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  • 18.
    Alexopoulos, Kosmas
    et al.
    University of Patras, Greece.
    Hribrenik, KarlBIBA - University of Bremen, Germany.Surico, MicheleFidia S.p.A., Italy.Nikolakis, NikolaosUniversity of Patras, Greece.Al-Najjar, BasimLinnaeus University, Faculty of Technology, Department of Mechanical Engineering.Keraron, YvesISADEUS, France.Duarte, MarcoINOVA+, Portugal.Zalonis, AndreasIntrasoft, Greece.Makris, SotirisLMS, Greece.
    Predictive maintenance technologies for production systems: A roadmap to development and implementation.2021Collection (editor) (Refereed)
    Abstract [en]

    High added-value products manufacturing methods are undergoing a continuous evolution nowadays, aiming to get higher productivity rates, product quality and reduction of defective products. Manufacturing companies increasingly use condition monitoring solutions and Predictive Maintenance (PdM) solutions to guarantee the intended usage of production equipment and to avoid unplanned downtimes. As such, this white paper presents a review of the lessons learned from the point of view of six EU funded H2020 research projects (PRECOM, PROPHESY, PROGRAMS, SERENA, UPTIME and Z-BREAK), funded under the topic “FOF-09-2017 - Novel design and PdM technologies for increased operating life of production systems”. These projects were active from 2017 to 2021 and together constituted the ForeSee cluster. Research and technology partners together with industrial end-users worked collaboratively to develop and deploy solutions that advance maintenance practice in industry towards more efficient, sustainable, human-centric and resilient factories. This white paper aims to share knowledge, vision and lessons learnt by ForeSee cluster partners on the topic of PdM, as well as to provide recommendations for advancing PdM in industrial practice. The core target groups of this report are industry practitioners, people in academia and policy makers at the local, national and EU levels.  The technologies that have acted as key-enablers in several of the ForeSee cluster projects (such as Internet of Things, Digital Twin, Proactive Computing, Virtual/Augmented Reality and linked data) are discussed in this document. Furthermore, the skilling of personnel, as well as the use of standardized technologies and processes are cross-cutting issues pertinent to ForeSee projects and their role in PdM projects is presented. The evaluation of these concepts and technologies in ForeSee industrial cases has proven their significance to industrial practice. The validation phase in industrial cases has served the ForeSee cluster with the provision of the following lessons learnt and recommendations for successful adoption of technology and best practices.  

    Lessons learned:

    ✓ Need for the development of structured data repositories with Industry4.0 and PdM datasets  

    ✓ Availability for testbeds for PdM, condition-based maintenance and intelligent asset management

    ✓ Adjustment of AI-based Maintenance and Asset Management Systems to facilitate accessibility by the non-experts

    ✓ Standardization, data and semantics interoperability, as necessary enablers to support the diverse software, hardware as well as business process landscape in asset management. Recommendations

    ✓ Business models for Condition Based Maintenance and Intelligent Asset Management should be further investigated

    ✓ Mobile Management - Mobile-First Condition Based Maintenance are important concepts that could benefit the adoption of CBM and PdM strategies  

    ✓ Smart and Autonomous Objects should be further considered when it comes to data collection, inspection, data collection and communication.  

    ✓ Adequate actions for Training - Education - Lifelong Learning of people working closely with advanced data and Internet of Things technologies should be considered.  (21) (PDF) Predictive maintenance technologies for production systems. A roadmap to development and implementation.

  • 19.
    Alfarraj, Mohamid
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Lewandowski, Sebastian
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Design and development of the light ramp2024Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis aims to enhance the light ramp of Rottne Industri AB's harvester. To achieve this, various theories and methodologies were applied throughout the project. By employing a systematic product development process, the authors were able to minimize manufacturing costs while incorporating additional features for improved functionality.

    The newly developed design resulted in several significant improvements. The height of the light ramp was reduced by 15%, which not only aligns with the project’s goals but also contributes to better integration with the machine's overall structure.

    The manufacturing costs have been lowered, making the production process more economical and efficient. Furthermore, the lighting coverage has been enhanced to provide better illumination of the nearby area that is surrounding the harvester, thereby increasing visibility and safety for the operator.

    Overall, the project successfully met all the set objectives, delivering a more efficient, cost-effective, and functional light ramp design for Rottne Industri AB’s harvester.

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  • 20.
    Algabroun, Hatem
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Dynamic sampling rate algorithm (DSRA) implemented in self-adaptive software architecture: a way to reduce the energy consumption of wireless sensors through event-based sampling2020In: Microsystem Technologies: Micro- and Nanosystems Information Storage and Processing Systems, ISSN 0946-7076, E-ISSN 1432-1858, Vol. 26, no 4, p. 1067-1074Article in journal (Refereed)
    Abstract [en]

    With the recent digitalization trends in the industry, wireless sensors are, in particular, gaining a growing interest. This is due to the possibility of being installed in inaccessible locations for wired sensors. Although great success has already been achieved in this area, energy limitation remains a major obstacle for further advances. As such, it is important to optimize the sampling with a sufficient rate to catch important information without excessive energy consumption, and one way to achieve sufficient sampling is using adaptive sampling for sensors. As software plays an important role in the techniques of adaptive sampling, a reference framework for software architecture is important in order to facilitate their design, modeling, and implementation. This study proposes a software architecture, named Rainbow, as the reference architecture, also, it develops an algorithm for adaptive sampling. The algorithm was implemented in the Rainbow architecture and tested using two datasets; the results show the proper operation of the architecture as well as the algorithm. In conclusion, the Rainbow software architecture has the potential to be used as a framework for adaptive sampling algorithms, and the developed algorithm allows adaptive sampling based on the changes in the signal.

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  • 21.
    Algabroun, Hatem
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    On the development of a maintenance approach for factory of the future implementing Industry 4.02017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The objective of this thesis is to develop a maintenance approach that fulfills the requirements of Industry 4.0. It explores the role and importance of maintenance activities in today’s industry. Then, it develops the features and tasks required to be performed by maintenance to fulfill the demands of Industry 4.0. Finally, it develops a reference model to be used in designing maintenance system for Industry 4.0. To perform these studies, real data were collected and applied as well as a typical scenario was implemented.

    The results achieved in the papers of this thesis are 1) a mathematical representation and application of a model that identifies, analyses and prioritizes economic weakness in working areas related to production, 2) a model that analyses, identifies and prioritizes failures that impact the competitive advantages and profitability of companies, 3) characterization of a suitable maintenance technique for Industry 4.0 and 4) a reference model i.e. a framework, that could be utilized to develop a maintenance approach for Industry 4.0.

    The conclusion of this thesis confirms that maintenance has a significant impact on companies’ competitive advantages, other working areas and profitability. To achieve a suitable maintenance technique for Industry 4.0, this technique must be able to monitor, diagnose, prognosis, schedule, assist in execution and present the relevant information. In order to perform these tasks several features must be acquired, the most important features are to be: digitized, automated, intelligent, able to communicate with other systems for data gathering and monitoring, openness, detect deviation in the condition at an early stage, cost- effective, flexible for adding new CM techniques, provide accurate decisions and scalable. The developed framework could be used as a base to design a maintenance system for Industry 4.0. This study contributes to our understanding of the maintenance importance in today’s industry and how to develop a maintenance approach for Industry 4.0.

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    Licentiate Thesis (Comprehensive Summary)
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  • 22.
    Algabroun, Hatem
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    On the development of a new digitalised maintenance approach for factories of the future2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over time, maintenance methods have developed following the dynamic manufacturers’ demands. Now, with the coming industrial revolution, new maintenance approaches have to be developed to fulfil the new demands of future industry, as well as to allow companies to benefit from technological advances. Therefore, the research question of this study is: how to develop a maintenance approach for factories of the future? To answer this question, this thesis proposes tools to identify and prioritise maintenance related problems that impact company’s profitability. It explores designing and implementation of a digitalised maintenance approach for future factories. Furthermore, it investigates tools and methods to collect data efficiently by sensors.

    The results achieved in this thesis are 1) a mathematical representation and application of a model that identifies and prioritises causes of deficiencies in production processes, 2) a model that identifies and prioritises failures that impact the competitive advantages and profitability of companies, 3) characterisation of a maintenance approach for future factories, 4) frameworks that could be utilised to develop a maintenance approach for future factories, as well as, guidelines that help to design this approach, 5) guidelines for the integration of digitalised maintenance with the database of other working areas, 6) an algorithm for adaptive sampling for sensors, as well as, a proposal for a generic software architecture to facilitate designing, modelling and implementation of adaptive sampling algorithms.

    The conclusion of this thesis confirms previous findings that maintenance has an impact on companies’ competitive advantages, other working areas and profitability. To design and implement a maintenance system, its elements should be extracted from the primary objective of maintenance. These elements should be then allocated in a suitable architecture and their mechanism should also be defined. Prior to implementation and integration, mapping the concept design to production problems can be used to examine its performance. An approach to collect data efficiently by sensors is to use adaptive sampling. The developed adaptive algorithm and the reference software framework for adaptive sampling algorithms could be used for this purpose.

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    Doctoral Dissertation (Comprehensive Summary)
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  • 23.
    Algabroun, Hatem
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Ingwald, Anders
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering. Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering.
    Assessment of the impact of maintenance integration within a plant using MFD: A case study2019In: Asset Intelligence through Integration and Interoperability and Contemporary Vibration Engineering Technologies: Proceedings of the 12th World Congress on Engineering Asset Management and the 13th International Conference on Vibration Engineering and Technology of Machinery / [ed] Joseph MathewC.W. LimLin MaDon SandsMichael E. CholettePietro Borghesani, Springer, 2019, p. 61-71Conference paper (Refereed)
    Abstract [en]

    In the recent decades the recognition of maintenance as an effective part of the company competitiveness has grown. In order to enhance maintenance performance and its positive impact, integration with the rest of the plant activities should be planned and performed. In this study, Maintenance Function Deployment model was applied on a real data of a case company. The model was used to analyse the company’s production with respect to the business and economic variables. This was done first through finding loss causes of the strategic goals of the case company, then breaking down these causes and their costs into their root causes. Based on economic estimations, the results show that the major root causes behind losses are insufficient training of personnel and lack of maintenance integration. It is concluded that properly considering the integration of maintenance within the company’s activities, reduces loss and improves the company’s performance. Also, that applying MFD eases the identification of the root-causes behind losses as well as quantifying and prioritizing the economic losses. © Springer Nature Switzerland AG 2019.

  • 24.
    Algabroun, Hatem
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Jonsson, Mikael
    E Maintenance Sweden AB, Sweden.
    A framework for the integration of digitalised maintenance systems with relevant working areas: A case study2020In: 4th IFAC Workshop on Advanced Maintenance Engineering, Services and Technologies - AMEST 2020 / [ed] Ajith Parlikad, Christos Emmanouilidis, Benoit Iung, Marco Macchi, Elsevier, 2020, Vol. 53, no 3, p. 185-190Conference paper (Refereed)
    Abstract [en]

    To enhance maintenance performance, maintenance integration with relevant activities should be planned and performed. In a digitalised industry, maintenance integration has to deal with various and heterogynous technologies. As the integration of such disparate technologies can be complex, this paper proposes a framework that provides the steps required for the successful integration of digitalised and automated maintenance across the relevant working areas. To develop this framework, we first identified relevant working areas to integrate maintenance with. Next, we identified integration success factors which are then considered in the framework development. The framework was then implemented in a real case study, and results showed that the integration tasks were completed successfully. Based on the case study, the framework provides guidelines for successfully integrating maintenance in a systematic way across the relevant working areas.

  • 25.
    Algabroun, Hatem
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Bokrantz, Jon
    Chalmers university of technology, Sweden.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Skoogh, Anders
    Chalmers university of technology, Sweden.
    Development of digitalised maintenance: a concept2022In: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 28, no 2, p. 367-390Article in journal (Refereed)
    Abstract [en]

    Purpose This paper presents a concept for digitalised maintenance (DM), maps the conceptualised DM to maintenance problems in industries and highlights challenges that might be faced when realizing this concept. Design/methodology/approach First, maintenance problems that are faced by the industry are presented, followed by a conceptualisation of DM. Next, a typical operational scenario is used as an exemplification to show system dynamics. The characteristics of this conceptualised DM are then mapped to the identified maintenance problems of industry. Then, interesting initiatives in this domain are highlighted, and finally, the challenges to realize this approach are discussed. Findings This paper identified a set of problems related to maintenance in industry. In order to solve current industrial problems, exploit emerging digital technologies and elevate future industries, it will be necessary to develop new maintenance approaches. The mapping between the criteria of DM and maintenance problems shows the potential of this concept and gives a reason to examine it empirically in future work. Originality/value This paper aims to help maintenance professionals from both academia and industry to understand and reflect on the problems related to maintenance, as well as to comprehend the requirements of a digitalised maintenance and challenges that may arise.

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  • 26.
    Algabroun, Hatem
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Iftikhar, Muhammad Usman
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Weyns, Danny
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Maintenance 4.0 Framework using Self: Adaptive Software Architecture2018In: Journal of Maintenance Engineering, Vol. 2, p. 280-293Article in journal (Refereed)
    Abstract [en]

    With the recent advances of manufacturing technologies, referred to as Industry 4.0, maintenance approaches have to be developed to fulfill the new de-mands. The technological complexity associated to Industry 4.0 makes designing maintenance solutions particularly challenging. This paper proposes a novel maintenance framework leveraging principles from self-adaptation and software architecture. The framework was tested in an operational scenario where a bearing condition in an electrical motor needs to be managed, the results showed a proper operation. As a conclusion, the proposed framework could be used to develop maintenance systems for Industry 4.0.

  • 27.
    Algabroun, Hatem
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Iftikhar, Muhammad Usman
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM).
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Weyns, Danny
    Linnaeus University, Faculty of Technology, Department of computer science and media technology (CM). Catholic University of Leuven, Belgium.
    Maintenance 4.0 Framework Using Self-Adaptive Software Architecture2017In: Proceedings of 2nd International Conference on Maintenance Engineering, IncoME-II 2017.The University of Manchester, UK, The University of Manchester, UK , 2017, , p. 299-309Conference paper (Refereed)
    Abstract [en]

    With the recent advances of manufacturing technologies, referred to as Industry 4.0, maintenance approaches have to be developed to fulfill the new de-mands. The technological complexity associated to Industry 4.0 makes designing maintenance solutions particularly challenging. This paper proposes a novel maintenance framework leveraging principles from self-adaptation and software architecture. The framework was tested in an operational scenario where a bearing condition in an electrical motor needs to be managed, the results showed a proper operation. As a conclusion, the proposed framework could be used to develop maintenance systems for Industry 4.0.

  • 28.
    Alhasan, Jenan
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Nguyen, Dat
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Kartläggning och förbättring av internt logistikflöde2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Globalisation has led to increased competition among companies, operating both locally and internationally. As a result, it has become crucial to stand out on the market by working cost-effectively, meeting customer requirements, offering short delivery times, smart material planning, among other things. New conditions, ranging from technological advancements to environmental demands, have prompted companies to focus on improving their material flow. The concept of logistics, along with lean-production, is now being recognized as a powerful tool. The purpose of this thesis is to gain a deeper understanding of wastes in a company's internal logistics flow and provide improvement suggestions for enhancing efficiency. The goal is to provide a foundation for future enhancements in the logistics flow of a manufacturing operation.

    To achieve the study's objectives and address the research questions, a case study is performed. The study will consist of a three-step plan. In the first stage, the problem is discussed, a literature study is carried out and suitable methods are identified. The next stage involves gathering information through interviews, observations, and documentation. Data is analysed and evaluated according to lean-principles. In the last phase, improvement proposals are developed based on the analysis. Theoretical approaches include deduction. The study employs both qualitative and quantitative research methods.

    The improvement suggestions are presented in the results chapter, categorized into general proposals, material handling, mapping, as well as a spaghetti diagram of the future state. The proposals focus on creating a continuous flow in production and minimizing security flaws. In addition, it is justified why a pulling-system and kanban-system should be introduced. The value stream mapping of the future state shows theoretically that the lead time can be halved if the stock size is minimized.

    The study analysed internal logistics waste and provided a basis for future projects. Using value stream mapping and spaghetti diagram, the authors successfully identified various improvement suggestions. For future research, it is recommended to include areas such as education, economic calculations, PDCA implementation, order and hook analysis, waste reduction, and optimal utilization of production space in the development process.

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  • 29.
    Alhasan, Tareq
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Gredelj, Adis
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Deformering av kuggar i planetväxlar2020Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [sv]

    Företaget SwePart i Liatorp har tagit fram en prototyp på en planetväxel utan glapp vilken kan gynna bl.a. robotindustrin. Problematiseringen är att växeln låter illa vid rotation vilket är vad som ska studeras i detta arbete.Syftet med det här arbetet är att studera reaktionskrafter mellan kuggarna samt kuggformens inverkan på jämnheten i växelns gång. Dessa studier kan leda till kunskap om orsaken till missljud vid interaktion mellan kuggar på planetväxlar. Målet är att få en större inblick i hur kuggarna påverkar varandra vid kontakt och momentöverföring.Studierna utförs genom simuleringar med hjälp av programmet MSC Adams, där SweParts prototypväxel analyseras genom att ta fram kontaktkrafter mellan ett planethjul och ringhjulet.Simuleringarna visar på stora hopp i amplituden under simuleringens tidsintervall vilket kan vara orsaken till missljud. Detta beror bl.a. på kuggarnas form.

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  • 30.
    Alkhatib, Tammam
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Robotic 3D Printing of sustainable structures2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis aims to integrate and evaluate a 3D printing robotic cell at the SmartIndustry Group – SIG lab at Linnaeus University (LNU).A sustainable structure consisting of wood fiber polymer composites was 3D printed withan industrial robot. Sustainable 3D printing material can be recycled or burned for energyafterwards. The 3D printing material used in this thesis stems from certificated forests.

    The objective is to utilise this technology in manufacturing courses and research projectsat the SIG lab at LNU. This objective is achieved by creating an operation manual and avideo tutorial in this thesis.The integration and evaluation process will involve offline robot programming,simulation, and practical experiments on the 3D printing robotic cell.

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  • 31.
    Allhorn, Simon
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Svensson, Victor
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Kapacitetsökning på ett producerande företag: Fallstudie på Villa VIDA AB2014Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    För att få en djupare förståelse för hur yta kan frigöras och användas har en studie genomförts på Villa VIDA som idag inte har tillräckligt med fri yta för kapacitetsökning. När nuläget analyserades kunde det konstateras att lagerbildningar på produktionsyta och ett måleri var det som hindrade företaget från att expandera. Baserat på det nuvarande läget genererades två alternativa layouter. I det ena förslaget valdes outsourcing av måleriet för att frigöra ännu mer yta och få plats med en kapacitetsökning på 50 % istället för 25 % som hade blivit resultatet om måleriet bevarats. Åtgärder som frigjorde yta innebar reducering av antal lagringspunkter och minskade orderkvantiteter. Vid utvärdering blev resultatet att företaget bör satsa på förslaget där måleriet är outsourcat då detta bidrar med ekonomiska så väl som flödesrelaterade fördelar samtidigt som ytan används på ett effektivare sätt.

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    Kapacitetsökning på ett producerande företag
  • 32.
    Alm Grundström, Henrik
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Litteraturstudie, modellering och simulering av kugginteraktioner i planetväxlar2015Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [sv]

    Detta arbete sammanfattar en del av den forskning som gjorts på kugghjul och planetväxlar med avseende på egenskaper som lastfördelning, verkningsgrad och ingreppsstyvheter. En jämförelse görs mellan olika metoder för beräkning av ingreppsstyvheter vilken visar på stora skillnader. En planetväxel av typ D simuleras i flerkroppsdynamikprogramvaran MSC ADAMS där egenskaper som lastfördelning, vridstyvhet och utväxling undersöks.

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  • 33.
    Alm, Gustav
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Johansson, Anton
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Värdeflödesanalys - Kartläggning & Effektivisering av Processflöden2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Continuous improvement and streamlining of processes are necessary to ensure that companies establish and maintain competitive advantage. To be able to streamline production, visualizations of processes are required to identify wastes and bottlenecks. A value stream map is a tool to visualize production processes and thereby enable the possibility to expose and eliminate wastes as well as bottlenecks. The goal of the study is therefore with the help of a value stream map give suggestions on methods to help streamline process flows at the case company.

    The study was conducted by observations, interviews, and literature documentation to ensure full validity and reliability. The study was based on two value flows for two different products and resulted in that the case company should consider decreasing tied up capital in inventories as well as upgrading internal systems such as the maintenance system.

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  • 34.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    A method and an apparatus for predicting the condition of amachine or a component of the machine2016Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    The present invention relates to a methodand an apparatus for predicting the condition of a machine or a component of the machine based on measurements of a condition monitoring parameter. The apparatus comprising a data storage for storing a moving window including measurement values of the condition monitoring parameter, a monitoring module configured to determine whena measurement value exceeds a potential failure level at which damage of the machine or component is considered initiated, and to determine the point in time (tP) when the monitoring parameter exceeded the potential failure level, a data cleaning module configured to discarda new measurement value if it is smaller than the latest stored measurement value inthe moving window, to determine an expected value for the measurement based on a defined pattern for the condition monitoring parameter, which pattern reflects an expected behavior of the monitoring parameter after damage has been initiated, and the time elapsed since the point in time the monitoring parameter exceeded the potential failure level, and to discard the new measurement value if it deviates too much from the expected value, and to store not discarded measurement values in the moving window, and a prediction module configured to predict the level of the condition monitoring parameter at a future point in time based on the measurement

  • 35.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    A universal coupling for transferring rotary movements between an inputshaft and an output shaft2016Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    The present invention relates to a universal coupling for transferring rotary movements between an input shaft and an output shaft (when the angel between the shafts can be about 90 degree), wherein each of the shafts are arranged to rotate about a longitudinal axis of the shaft, the coupling comprising: an input joint member and output joint member movably coupled to each, and the input joint member  is fixedly connected to the input shaft and the output joint member is fixedly connected to the output shaft.  Each of the input and output joint members comprises at least one annular part having a cross section and defining a central aperture, the annular part of the input joint member passes through the aperture of the annular part of the output joint member, and the annular part of the output joint member passes through the aperture of the annular part of the input joint member, and the area of each the central apertures is larger than the cross section area of each of the annular parts and two spaced apart contact points are formed between the annular parts of the input and output joint members.

  • 36.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    CBM Today and Tomorrow: A Model for Digitalised, Automated and Intelligent CBM Exemplified for VBM2017In: Proceedings of 2nd International Conference on Maintenance Engineering, IncoME-II 2017.The University of Manchester, UK, The University of Manchester, UK , 2017 / [ed] Jyoti K. Sinha, Manchester, UK: The University of Manchester, UK , 2017, p. 262-273, article id ME2017_1132Conference paper (Refereed)
    Abstract [en]

    Industry strives towards developing and implementing digitalised and automated production process, Industry 4.0. This states hard terms and conditions to develop new concept-based maintenance to meet the new production process demands. Intelligent and automated condition-based maintenance (CBM) exempli-fied in vibration-based maintenance (VBM) is one of the most suitable techniques for developing a maintenance concept fulfilling the demands stated by Industry 4.0. In this paper, we identified today´s VBM-process activities and their applica-tion, and introduced and discussed their status. In addition, we developed a model that describes future VBM, Cognitive VBM. Then, we compared cognitive VBM with the currently available VBM. The major conclusions are the potential benefit of applying Cognitive VBM is the continuous enhancement of company internal effectiveness in a cost-effective way.

  • 37.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    CBM Today and Tomorrow: A Model for Digitalised, Automated and Intelligent CBM Exemplified for VBM2018In: Journal of Maintenance Engineering, Vol. 2, p. 243-256Article in journal (Refereed)
    Abstract [en]

    Industry strives towards developing and implementing digitalised and automated production process, Industry 4.0. This states hard terms and conditions to develop new concept-based maintenance to meet the new production process demands. Intelligent and automated condition-based maintenance (CBM) exempli-fied in vibration-based maintenance (VBM) is one of the most suitable techniques for developing a maintenance concept fulfilling the demands stated by Industry 4.0. In this paper, we identified today´s VBM-process activities and their applica-tion, and introduced and discussed their status. In addition, we developed a model that describes future VBM, Cognitive VBM. Then, we compared cognitive VBM with the currently available VBM. The major conclusions are the potential benefit of applying Cognitive VBM is the continuous enhancement of company internal effectiveness in a cost-effective way.

  • 38.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Condition based maintenance for mechanical systemsManuscript (preprint) (Other academic)
    Abstract [en]

    In this paper a sequential method for the selection of maintenance technique for mechanical systems is presented. It is based on technical knowledge concerning component failure mechanisms and failure causes. Classification of failures according to their consequences is stated. A modified version of failure modes, effects and criticality analysis is given and a way to identify significant components is discussed. Analysis of collected data is discussed and a method to identify a replacement level of a monitoring parameter is proposed. Criteria for the selection of a monitoring technique based on the intrinsic information of monitoring parameters are introduced. Finally, a decision rule for the selection of a suitable maintenance technique is suggested and a modified expression of the long run average cost per unit time is used as a distinguishing criterion between applicable strategies.

  • 39.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Determination of potential failure initiation time using cumulative sum chart2016In: IFAC-PapersOnLine / [ed] Christos Emmanouilidis, Benoît Iung, Marco Macchi and François Pérès, Elsevier, 2016, Vol. 49:28, p. 43-48Conference paper (Refereed)
    Abstract [en]

    Hard competition forces companies to reduce uncertainty in production planning through, e.g. reducing the probability of failures. In this paper, more accurate data analysis through reducing randomness in vibration measurements is introduced. Quality control tool Cumulative Sum (Cusum) Chart is adapted for monitoring variation in vibration level to determine the time of potential failure initiation. The result confirms the possibility of reducing false alarms arise due to randomness in vibration signals. The major conclusion; applying Cusum chart it is possible to determine the time of initiation of a potential failure for follow up its progression and accurate planning of maintenance.

  • 40.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    En metod och en apparat för att prediktera tillståndet hos en maskin eller en komponent hos maskinen: PreVib algorithm2014Patent (Other (popular science, discussion, etc.))
    Abstract [sv]

    Ett ändamål med föreliggande uppfinning är att förbättra prediktionen av en tillstånds­övervaknings­parameter och därmed förbättra uppskattningen av den mest effektiva tidpunkten för att byta ut eller utföra underhåll på en maskin eller viktiga komponenter hos maskinen.

    Mätdata som används för predikteringen renas på ett sådant sätt att en optimal prediktering uppnås. Om någon del av maskinen är skadad borde mätningarna öka eftersom skadan i maskin­komponenten är irreversibel, d.v.s. den kan inte laga sig själv, vilket borde medföra att värdena på mätningarna inte kan minska över tiden. De utvalda värdena sparas i ett rörligt fönster anpassat att spara ett förutbestämt antal mätvärden.

    Predikteringen börjar när värdet av den uppmätta tillstånds­övervaknings­parametern har överstigit en potentiell skadenivå, d.v.s. skada har initierats, vid vilken det antas att en potentiell skada hos maskinen eller komponenten är initierad. Det förväntade värdet bestäms baserat på ett fördefinierat mönster som reflekterar ett förväntat beteende hos den övervakade parametern efter det att skada har initierats, och tiden som har förflutit mellan tidpunkten när mätningen utfördes och tidpunkten när övervakningsparametern översteg den potentiella skadenivån. Mätvärdena måste på så sätt uppfylla två olika villkor för att de ska tillåtas att sparas i det rörliga fönstret. 

    Predikteringen utförs baserat på mätvärden som sparas i det rörliga fönstret, dvs. som är renade från störningar. På så sätt förbättras predikteringen.

    På grund av det faktum att mätdata renas också under den första fasen är det möjligt att starta prediktionen baserat på mätvärdena som sparats i det rörliga fönstret så fort som värdet på övervakningsparametern har passerat den potentiella skadenivån. På så sätt baseras prediktionen på mätvärden sparade under den första fasen såväl som under den andra fasen.

    Tack vare reningen av mätvärdena minskas antalet nödvändiga mätningar för att åstadkomma en tillräckligt bra prediktering. Det är tillräckligt med tre mätvärden som har renats enligt uppfinningen för att få ett tillförlitligt resultat.

    Enligt en utföringsform av uppfinningen är det fördefinierade mönstret för tillstånds­övervaknings­parametern en kurva som börjar öka vid tidpunkten då övervaknings­parametern överstiger den potentiella skadenivån. Kurvan beskriver värdet hos övervaknings­parametern i förhållande till tiden som har förflutit sedan tidpunkten då övervakningsparametern översteg den potentiella skadenivån. Formen på mönstret och således på kurvan beror t.ex. på typen av parameter, typen av skada, t.ex. ett brott eller slitage, och typen av förslitningssprocess, maskinens last och hastighet, och typen och kvalitén hos maskinen eller komponenten. För många typer av fel är kurvan exponentiellt ökande. Kurvan bestäms t.ex. baserat på föregående värde för samma tillståndsövervakningsparameter för samma eller liknade typer av maskiner eller komponenter. Kurvan börjar vid samma tid som det har detekterats att en skada har initierats, d.v.s. vid den tidpunkten då övervakningsparametern överstiger den potentiella skadenivån, och kurvan ökar under hela den andra fasen. Det förväntade värdet av mätningen bestäms baserat på kurvan och tidpunkten för mätningen. På sätt är det lätt att bestämma det förväntade värdet på mätningen.

    Enligt en utföringsform av uppfinningen slängs det nya mätvärdet om mätvärdet avviker från det förväntade värdet med mer än ett gränsvärde, gränsvärdet kan vara förutbestämt eller beräknas dynamiskt under den andra fasen.

    Enligt en utföringsform av uppfinningen innehåller mätmetoden vidare: ett meddelande till användaren genereras för att kontrollera mätningen och tillhandahålla ett nytt mätvärde när man har upptäckt att mätvärdet avviker för mycket från det definierade mönstret, ett nytt mätvärde tas emot och det nya mätvärdet jämförs med det förväntade värdet som har bestämts i enlighet med det definierade mönstret för tillstånds­övervaknings­parametern, och en varning genereras om det nya mätvärdet också avviker för mycket från det förväntade värdet. I annat fall byts det äldsta av de sparade mätvärdena i det rörliga fönstret ut mot det nya mätvärdet. En ny mätning utförs om värdet på mätningen avviker för mycket från det förväntade värdet under den andra fasen. Alternativt tas ett nytt mätvärde automatiskt när det har detekterats att en mätning avviker för mycket från det förväntade värdet. I och med denna utföringsform kastas ett felaktigt mätvärde och ersätts med en ny förslitningsrelevant mätning. Om den nya mätningen också avviker för mycket från det förväntade värdet genereras en varning till användaren. Det kan antigen betyda att någonting är fel med mätutrustningen eller att skadan har utvecklats mycket fortare än förväntat och att en underhållsåtgärd brådskande behöver utföras.

    Enligt en utföringsform av uppfinningen innefattar metoden vidare: den predikterade nivån hos tillstånds­övervaknings­parametern jämförs med åtminstone ett gränsvärde för tillstånds­övervaknings­parametern, de föregående stegen upprepas åtminstone tills den predikterade nivån hos tillstånds­övervaknings­parametern överstiger gränsnivån och ett meddelande genereras avseende en underhållsåtgärd när den predikterade nivån hos tillstånds­övervaknings­parametern överstiger gränsnivån. Gränsnivån är t.ex. en varningsnivå som ligger nedanför utbytesnivån för komponenten eller maskinen. Det är också möjligt att ha flera gränsnivåer mellan den potentiella skadenivån och en utbytesnivå. Denna utföringsform gör det möjligt att föreslå en underhållsåtgärd med tillräcklig ledtid vid en kostnadseffektiv tidpunkt.

    Enligt en utföringsform av uppfinnen är maskinen en roterande maskin och mätvärdena någon av vibrationsmätningar, temperaturmätningar, ljudmätningar och chockpulsmätningar.

    Enligt en annan aspekt av uppfinningen uppnås detta ändamål av en datorprogramprodukt direkt nedladdningsbar i det interna minnet hos en dator, eller genom en fjärrstyrd dator, web-service, eller molntjänst innefattande mjukvara för att utföra stegen hos metoden när nämnda program körs på datorn.

    Enligt en annan aspekt av uppfinningen uppnås detta ändamål av ett dataläsbart medium som har ett program inspelat, där programmet får datorn att utföra stegen i metoden när programmet körs på datorn.

    Enligt en annan aspekt av uppfinningen uppnås detta ändamål av en apparat.

  • 41.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Just-in time and dynamic maintenance (JIT-Maint) for turbine, generator, gearbox and sawmills: case stories2015In: 28º COMADEM + X CORENDE 2015 / [ed] Marta Clelia Ruch, Asociación Argentina de Ensayos no Destructivos y Estructurales, AAENDE , 2015Conference paper (Refereed)
    Abstract [en]

    Profitable production demands continuously improved maintenance decision accuracy to reduce unplanned stoppages, prolong components/machines  life length and maintain production continuity. When CM, e.g. vibration level or oil temperature, value exceeds a warning level, it demands a clear understanding of what happened and how it will develop to avoid failures. It demands also reliable information, e.g. probability of failure, residual  life and when is the most profitable time for maintenance. Companies strive to reduce production cost through reducing non-value adding times, e.g. failures, for offering customers lower prices and generating additional competitive advantages. In this paper, a new tool (Prediction of Vibration and oil temperature, PreVib) for predicting the condition of a turbine, generator and gearbox is introduced,  discussed and tested. The solution offers a unique opportunity to achieve just in time dynamic and cost-effective maintenance by selecting the most profitable time for maintenance. PreVib is tested in a power plant. The major results: Failures can appreciably be reduced thanks the high precision of prediction ( + 90%), i.e. a negligible difference from the real measurement: PreVib does not demand extensive or additional data, and not replace available maintenance systems. The major conclusion is that applying PreVib, it is possible to reduce failures appreciably, prolong life length of components/equipment and perform profitable maintenance

  • 42.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    More Reliable Profitable and Competitive Production via Effective e-Maintenance: A Case Study2015In: Proceedings of the 7th World Congress on Engineering Asset Management (WCEAM 2012) / [ed] Woo Bang Lee,Byeongkuen Choi, Lin Ma and Joseph Mathew, Switzerland: Springer, 2015, p. 49-59Chapter in book (Refereed)
    Abstract [en]

    Profitable production demands continuously improved maintenance decision accuracy for reducing/avoiding failures and unplanned stoppages due to their consequences. More accurate decisions prolong life length of components and consequently machines, and maintain the production running longer. When a condition monitoring (CM) value exceeds a significant (warning) level it demands a clear understanding of what happened and how it will develop in the next future to avoid failures. Also, CM demands reliable information concerning the probability of failure, residual life time and when is the most profitable time of conducting maintenance. Companies strive to reduce production cost in order to increase the possibility of offering customers lower prices & generating additional competitive advantages. But, applying new technologies for enhancing maintenance and production performances and company competitiveness counter many problems in industry. In this paper, a new innovative e-Maintenance Decision Support System (eMDSS) is introduced and discussed; the problems facing successful implementation of eMDSS based on a case study are introduced and discussed. Solutions to avoid the problems facing successful implementation of e MDSS are suggested and discussed. eMDSS offers a unique opportunity to achieve just in time dynamic and cost-effective maintenance by selecting the most profitable time for maintenance. It offers innovative solutions to increase maintenance profitability by enhancing maintenance decision accuracy via:

    1. Identifying & classifying problems based on their shares in losses in production.

    2. Predicting the value of CM parameter, e.g. vibration, level in the near future.

    3. Estimating the probability of failure and component remaining life in the near future.

    4. Estimating the most profitable time for maintenance action.

    5. Selecting the most profitable maintenance action.

    6. Mapping & following up maintenance & production performances.

    7. Identifying and following up the most profitable investment in maintenance.

    eMDSS combines technical and economic data describing future situation in addition to the current & past data, which is necessary for production and maintenance successful planning. The major conclusion is that applying eMDSS it is possible to reduce failures appreciably, prolong life length of components/equipment & perform profitable maintenance

  • 43.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    On a graphical method for the selection of a maintenance techniqueManuscript (preprint) (Other academic)
    Abstract [en]

    In this paper a graphical method for the selection of a cost-effective monitoring technique is suggested. Also, a graphical method to estimate the level at which components should be replaced when using a cost-effective technique, i.e. threshold level, is proposed. These two methods are based on the concept of the Total Time on Test, TTT-plot on age and condition dependent replacement is discussed.

  • 44.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    On the modelling of condition dependent failure rates in mechanical systemsManuscript (preprint) (Other academic)
    Abstract [en]

    The cycle between two replacements based on condition monitoring is discussed. Models representing a condition dependent failure rate function reflecting the information in a monitoring parameter are suggested. For the selection of a cost-effective technique, a modified version of the Proportional Hazards Model, PHM, is proposed. Utilizing this modified model, it is possible to reveal the effect of monitoring parameters and operating conditions on the failure rate function. General comments on the application of the cost equation are given.

  • 45.
    Al-Najjar, Basim
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Aiyshwaryaa, Z
    Astra Zeneca, Sweden.
    Patel, Mina
    Astra Zeneca, Sweden.
    Kattepur, Ajay (Contributor)
    Ericsson, Sweden.
    Nair, Anil (Contributor)
    Ericsson, Sweden.
    Selvan, Arvind (Contributor)
    Uppsala University, Sweden.
    Jonsson, Mikael (Contributor)
    E-Maintenance Sweden AB, Sweden.
    SmartPro Vinnova Report2021Report (Refereed)
    Abstract [en]

    This report presents the findings of WP2 with respect to challenges and use-cases relevant to smart production and maintenance systems. WP2 gathers information and determines the challenges the industrial partners (Astra Zeneca and Ericsson) in Sweden and India have. These challenges have been translated into concrete problems and purposes, which finally describes a main project problem and purpose. WP2 also focuses on specific use cases where smart automation and information gathering can help relieve potential bottlenecks. An exhaustive study of technologies and challenges has also been included. It is the view of WP2 that smart production maintenance technologies should be bundled with other solutions to have an increased impact within factory production systems. At the current stage, production maintenance is a secondary aspect in both Astra Zeneca and Ericsson factories.

  • 46.
    Al-Najjar, Basim
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Algabroun, Hatem
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    A Model for Increasing Effectiveness and Profitability of Maintenance Performance: A Case Study2018In: Engineering Asset Management 2016: Proceedings of the 11th World Congress on Engineering Asset Management, Springer, 2018, p. 1-12Conference paper (Refereed)
    Abstract [en]

    In today’s market, companies strive to achieve the competitive advantages. Failing in achieving these goals could threaten the companies’ existence. Failures in the operative level impact negatively on achieving these goals. In order to record these failures for better actions planning, special systems are often used for counting the number of failures, registering the duration of machines downtime and uptime for assessing the total downtime and classifying problems/failures in categories that are decided in advance. These categories can be Electrical, Electronic, Hydraulic, Mechanical, Pneumatics, Human error, and Miscellaneous. In this study, we develop a model to break down the contents of a company/machine failure databases, prioritize failures, assess economic losses due to failure impact on the competitive advantages and suggest a method of how maintenance actions should be rank-ordered cost-effectively. The model is tested using real data. The major results showed that losses aremainly due to two categories i.e. “Bad quality“ and “Less profit margin”, where failures of “Gear”, “Bearing” and “Raw materials quality” cause most of the losses. It is concluded that this model enables the user to quickly identify and prioritize maintenance and improvement efforts cost-effectively.

  • 47.
    Al-Najjar, Basim
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Algabroun, Hatem
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Jonsson, Mikael
    E-maintenance Sweden AB, Sweden.
    Maintenance 4.0 to fulfil the demands of Industry 4.0 and Factory of the Future2018In: International Journal of Engineering Research and Applications, E-ISSN 2248-9622, Vol. 8, no 11, p. 20-31Article in journal (Refereed)
    Abstract [en]

    In today's high market competition, industries attempt adapt new technologies retain their market share. With technology advancement in factories, maintenance methods are developed to suit the new manufacturers. demands. Now, with the Industry 4.0, new maintenance techniques have to be developed to fulfill the new demands which we refer to as Maintenance 4.0. Each currently used maintenance technique has its own advantages and disadvantages. Until now it is unclear if these techniques are suitable for Industry 4.0. This study shows how to identify the maintenance technique that is the most suitable to be further developed for Industry 4.0. In this paper, the tasks and features of Maintenance 4.0 are identified, and the suitability of the most popular maintenance techniques is examined with respect to Industry 4.0 demands. This is done by using Multiple Attribute Decision Making combined with the Simple Additive Weight. The results show that Total Quality Maintenance(TQMain) and then Condition Based Maintenance(CBM) are the highest ranked among the examined maintenance techniques, and therefore it is concluded that these maintenance techniques could be used as a based to develop Maintenance 4.0.

    Download full text (pdf)
    Maintenance 4.0 to fulfil the demands of Industry 4.0 and Factory oftheFuture
  • 48.
    Al-Najjar, Basim
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Algabroun, Hatem
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Jonsson, Mikael
    E-maintenance Sweden AB, Sweden.
    Smart maintenance model using cyber physical system2018In: Paper presented at the International Conference on "Role of Industrial Engineering in Industry 4.0 Paradigm" (ICIEIND), Bhubaneswar, India, September 27-30, 2018, 2018, p. 1-6Conference paper (Refereed)
    Abstract [en]

    Modern manufacturing are exposed to rapid and dynamic changes in operating conditions, market demands, national and international competition. Therefore, new generations and concepts of maintenance techniques are necessary to overcome the deficiencies  in the current techniques. The purpose of this paper is to propse a maintenance model that is automatic, digitzalised and intelligent using Cyber Physical System (CPS-Maint). In this paper, we presented comparable maintenance approaches and described their shortages. Thereafter, we developed a new maintenance model. Then, A simulation using LabVIEW is conducted  to examin the model and its behavior. The results showed that the required tasks are performed with no conflict among its components. The major result is the development of CPS-Maint and the major conclusion is applying CPS-Maint fulfills industry needs. This paper provides a framework that could help developers and researchers in desining and developing an automatic and smart maintenance system.

    Download full text (pdf)
    Smart Maintenance Model using Cyber Physical System
  • 49.
    Al-Najjar, Basim
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Ingwald, Anders
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Kans, Mirka
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Maintenance in Real Estate and Manufacturing Industries: Differences, Problems, Needs and Potentials - Four Case Studies2016In: Proceedings of the 10th World Congress on Engineering Asset Management (WCEAM 2015) / [ed] Koskinen, KT; Kortelainen, H; Aaltonen, J; Uusitalo, T; Komonen, K; Mathew, J; Laitinen, J, Switzerland: Springer, 2016, p. 13-27Conference paper (Refereed)
    Abstract [en]

    It is about 50 % of the activities in the housing sector in the EU region are related to maintenance. According to several publications, building management systems are still quite rare and efficient methodologies for service life prediction of building parts still need to be developed. Also, recent studies show difficulties in finding comprehensive answers concerning, e.g. identifying risks and preventive maintenance actions. Incomplete information can easily lead to incorrect maintenance actions. The problem addressed is: How to improve performance and cost-effectiveness of the maintenance applied on real estate facilities especially buildings to reduce maintenance and management costs and increase company profit? The study’s objectives are to analyse maintenance; techniques, costs, weaknesses and potentials, and compare it with manufacturing industry experience. Also, to investigate whether there is a need for a DSS for planning and follow up cost-effective CBM. The major results of four case studies are; (1) Preventive and breakdown maintenance are mainly used and actions are funded from different accounts. (2) The concept of cost-effectiveness is applied occasionally. (3) Lack of CBM-DSS for planning, follow up and evaluate maintenance profitability, and cost-effective improvements of company business and tenant living quality. (4) The profit generated by continuous heating of building thanks efficient maintenance is about 2.332 million SEK. The major conclusion; there is a reasonable opportunity to reduce buildings’ management and maintenance costs.

  • 50.
    Al-Najjar, Basim
    et al.
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Jacobsson, Martin
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. LNU.
    A computerised model to enhance the cost-effectiveness of production and maintenance dynamic decisions: A case study at Fiat2013In: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 19, no 2, p. 114-127Article in journal (Refereed)
    Abstract [en]

    Purpose:

    – To develop and test a model and software-based support system for better understanding

    of the interactions between man-machine-maintenance-economy (MMME), and enable cost-effective decisions.

    Design/methodology/approach:

    – The study is based on published knowledge and experience within maintenance, maintenance organization and production, and a case study.

    Findings:

    – Development of a model describing interactions between man-machine-maintenance-economy interactions and MMME software module. MMME test shows its ability to identify, quantify, assess and follow up losses in production time which is necessary when planning effective maintenance actions.

    Research limitations/implications:

    – In the paper the focus is to quantify production time losses in order to identify the root causes of the problem. The case study is performed at a manufacturing plant for truck engines.

    Practical implications:

    – A systematic approach of how to quantify and evaluate losses in production time in order to identify problems and problem areas within the production. This approach is discussed and motivated with the aim of achieving more cost-effective decisions in maintenance.

    Originality/value:

    – The model and software application developed enables a structured way of analyzing production time losses in order to find cost-effective solutions to the problems. The model is very flexible enabling it to be customized for a wide spectrum of branches.

     

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