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  • 1.
    Abdeljaber, Osama
    et al.
    Qatar University, Qatar.
    Sassi, Sadok
    Qatar University, Qatar.
    Avci, Onur
    Qatar University, Qatar.
    Kiranyaz, Serkan
    Qatar University, Qatar.
    Ibrahim, Abdelrahman
    Qatar University, Qatar.
    Gabbouj, Moncef
    Tampereen University of Technology, Finland.
    Fault Detection and Severity Identification of Ball Bearings by Online Condition Monitoring2019In: IEEE transactions on industrial electronics (1982. Print), ISSN 0278-0046, E-ISSN 1557-9948, Vol. 66, no 10, p. 8136-8147Article in journal (Refereed)
    Abstract [en]

    This paper presents a fast, accurate, and simple systematic approach for online condition monitoring and severity identification of ball bearings. This approach utilizes compact one-dimensional (1-D) convolutional neural networks (CNNs) to identify, quantify, and localize bearing damage. The proposed approach is verified experimentally under several single and multiple damage scenarios. The experimental results demonstrated that the proposed approach can achieve a high level of accuracy for damage detection, localization, and quantification. Besides its real-time processing ability and superior robustness against the high-level noise presence, the compact and minimally trained 1-D CNNs in the core of the proposed approach can handle new damage scenarios with utmost accuracy.

  • 2.
    Abu-Ragheef, Basil
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Polymer Aging Mechanics: An investigation on a Thermoset Polymer used in the Exterior Structure of a Heavy-duty Vehicle2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The use of plastic materials in the design of vehicle components is primarily driven by the need for vehicle weight and cost reduction. Additionally, these materials give design engineers freedom in creating appealing exterior designs. However, creating self-carrying exterior structures with polymers must fulfill long-term strength, creep and fatigue life requirements. Thus, the polymer polyDicyclopentadiene (pDCPD) has been chosen for this purpose. Its aging mechanics need to be understood by the design engineers to make the right decisions. This thesis has carried out mechanical tests such as uniaxial tensile testing, fatigue, and creep testing. Digital image correlation (DIC) system has been used to capture strain data from tensile tests. In the final analysis, DIC measurements proved more accurate than extensometer data retrieved from the testing machine. The rise in temperature has been captured using thermal imaging. Several degradation processes have been explored including physical aging, thermo-oxidation, photo-oxidation, chemical- and bio- degradations. Test results showed significant changes in mechanical properties after 17 years of aging. Additionally, severe thermal degradation has been observed in one of the tested panels of pDCPD. Temperature can rise to significant levels during cyclic loading at high stresses, which could have an impact on physical aging effects. Viscoelastic behavior has been explored and changes in dynamic and creep properties have been observed. The investigation also reviled that different defects caused by flawed manufacturing also can affect the material severely as one case has proved in this research.

  • 3.
    Adam, Stenlund
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    John, Barnekow
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Energieffektivisering av Ronneby is-arena samt vädrets termodynamiska påverkan2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Today Sweden has 341 ice hockey arenas, around 140 outdoor ice hockey rinks, 60 ice fields for bandy and about 35 curling arenas. In addition, the numbers of indoor bandy arenas are increasing. The cooling systems installed today should be able to lower its energy consumption with 10-30%.In this thesis, Ronneby ice-arena has been researched. This artificial cooling facility was inaugurated 2011 and is one of the newest in Sweden. This is an outdoor ice field for bandy and therefor has no roof or walls to cover the field. Ronneby ice-arena has problems with uneven cooling distribution of the ice field. This results in cracks and uneven ice quality. These problems also result in higher energy consumption than necessary.To find a solution for the uneven cooling of the ice field flow measurements were carried out in the brine circuit. To get a better understanding of the cooling distribution, temperature measurements were carried out on the brine feeding lines. A calculation has been performed on what energy savings a speed control of the brine circulation pumps depending on the outdoor temperature could generate. Another calculation was made to see the possible savings with a windshield around the field. In this thesis the benefits of a heat recovery system on the cooling compressors refrigerant has been investigated. The heat recovery system could heat the locker rooms, the clubhouse, the showers and the hot water for the Zambonis.In order to perform the necessary calculation for this thesis, Fredriksbergs BK and Ronneby municipality provided operating data.The actions proposed to Ronneby ice-arena to solve the uneven cooling of the ice field is to change the location of the brine feeding line connection point. At the same time this work is carried out it’s suggested that the brine feed and return lines get insulated. When the uneven cooling problems have been solved, a speed control system should be installed to control the brine circulation pumps, in order to lower the electricity consumption. Ronneby ice-arena has the possibility to install a heat recovery system. Therefore it is suggested to install a heat exchanger on each cooling compressor refrigerant. This installation is to be used to heat the clubhouse, the showers and the hot water for the Zambonis. The system to cool the condensers with seawater and currently the heat pump are not optimal designed. The installed heat pump does not work when the seawater temperature is below 5°C, therefore the system should be redesigned.

  • 4.
    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.

  • 5.
    Ahlgren, Fredrik
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Reducing ships' fuel consumption and emissions by learning from data2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the context of reducing both greenhouse gases and hazardous emissions, the shipping sector faces a major challenge as it is currently responsible for 11% of the transport sector’s anthropogenic greenhouse gas emissions. Even as emissions reductions are needed, the demand for the transport sector rises exponentially every year. This thesis aims to investigate the potential to use ships’ existing internal energy systems more efficiently. The thesis focusses on making existing ships in real operating conditions more efficient based logged machinery data. This dissertation presents results that can make ship more energy efficient by utilising waste heat recovery and machine learning tools. A significant part of this thesis is based on data from a cruise ship in the Baltic Sea, and an extensive analysis of the ship’s internal energy system was made from over a year’s worth of data. The analysis included an exergy analysis, which also considers the usability of each energy flow. In three studies, the feasibility of using the waste heat from the engines was investigated, and the results indicate that significant measures can be undertaken with organic Rankine cycle devices. The organic Rankine cycle was simulated with data from the ship operations and optimised for off-design conditions, both regarding system design and organic fluid selection. The analysis demonstrates that there are considerable differences between the real operation of a ship and what it was initially designed for. In addition, a large two-stroke marine diesel was integrated into a simulation with an organic Rankine cycle, resulting in an energy efficiency improvement of 5%. This thesis also presents new methods of employing machine learning to predict energy consumption. Machine learning algorithms are readily available and free to use, and by using only a small subset of data points from the engines and existing fuel flow meters, the fuel consumption could be predicted with good accuracy. These results demonstrate a potential to improve operational efficiency without installing additional fuel meters. The thesis presents results concerning how data from ships can be used to further analyse and improve their efficiency, by using both add-on technologies for waste heat recovery and machine learning applications.

  • 6.
    Ahlgren, Fredrik
    et al.
    University of Kalmar, Kalmar Maritime Academy.
    Ahlgren, Kristoffer
    University of Kalmar, Kalmar Maritime Academy.
    Gasens inverkan på oljan i ett hydrauliksystem2009Independent thesis Basic level (degree of Bachelor), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    I detta arbete har vi med en litteraturstudie försökt påvisa vad en inblandad gas i oljan i ett hydrauliksystem har för betydelse för funktionen. Vi har använt information i traditionell facklitteratur samt i tidskrifter och vetenskapliga rapporter och upptäckt att problemen som uppkommer av inblandade gaser inte är väl kända. Dagens lösningar på problemen är nästan alltid kostsamma och handlar om att behandla symptomen. Vi har tittat på de olika fysikaliska data som gasen inverkar på i oljan, utifrån detta har vi analyserat vilka effekter detta har för ett hydrauliksystems funktion. Vi kommer att diskutera grundproblemet till kavitation och vanliga problem som ett hydrauliksystem ofta har. Vi har lyckats presentera resultat på att inblandad gas i oljan har en mycket stor inverkan på ett hydrauliksystem. Vi har kommit fram till att mycket av dagens problem med hydrauliksystem helt skulle kunna byggas bort om man tog större hänsyn till oljans förmåga att lösa in luft.

  • 7.
    Ahlgren, Fredrik
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Mondejar, Maria E.
    Technical University of Denmark, Denmark.
    Thern, Marcus
    Lund University, Sweden.
    Predicting dynamic fuel oil consumption on ships with automated machine learning2019In: Innovative Solutions for Energy Transitions: Proceedings of the 10th International Conference on Applied Energy (ICAE2018) / [ed] Prof. J.Yanab, Prof. H.Yang, cDr. H.Lid, Dr. X.Chene, Elsevier, 2019, Vol. 158, p. 6126-6131Conference paper (Refereed)
    Abstract [en]

    This study demonstrates a method for predicting the dynamic fuel consumption on board ships using automated machine learning algorithms, fed only with data for larger time intervals from 12 hours up to 96 hours. The machine learning algorithm trained on dynamic data from shorter time intervals of the engine features together with longer time interval data for the fuel consumption. To give the operator and ship owner real-time energy efficiency statistics, it is essential to be able to predict the dynamic fuel oil consumption. The conventional approach to getting these data is by installing additional mass flow meters, but these come with added cost and complexity. In this study, we propose a machine learning approach using auto machine learning optimisation, with already available data from the machinery logging system.

  • 8.
    Ahlgren, Fredrik
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Thern, Marcus
    Lunds Tekniska Högskola.
    Auto Machine Learning for predicting Ship Fuel Consumption2018In: Proceedings of ECOS 2018 - the 31st International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems, Guimarães, 2018Conference paper (Refereed)
    Abstract [en]

    In recent years, machine learning has evolved in a fast pace as both algorithms and computing power are constantly improving. In this study, a machine learning model for predicting the fuel oil consumption from engine data has been developed for a cruise ship operating in the Baltic Sea. The cruise ship is equipped with legacy volume flow meters and newly installed mass flow meters, as well as an extensive set of logged time series data from the machinery logging system. The model is developed using state-of-the-art Auto Machine Learning tools, which optimises both the model hyper parameters and the model selection by using genetic algorithms. To further increase the model accuracy, a pipeline of different models and pre-processing algorithms is evaluated. An extensive model trained for a certain system can be used for optimisation simulation, as well as online energy efficiency prediction. As the models automatically adapt to noisy sensor data and thus function as a watermark of the machinery system, these algorithms show a potential in predicting ship energy efficiency without installation of additional mass flow meters. All tools used in this study are Open Source tools written in Python and can be applied on board. The study shows great potential for utilising large amounts of already available sensor data for improving the accuracy of the predicted ship energy consumption.

  • 9.
    Ahlgren, Fredrik
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Thern, Marcus
    Lund University.
    Genrup, Magnus
    Lund University.
    Mondejar, Maria E.
    Technical University of Denmark, Denmark.
    Energy integration of organic rankine cycle, exhaust gas recirculation and scrubber2018In: Trends and challenges in maritime energy management / [ed] Aykut I. Ölçer, Momoko Kitada, Dimitrios Dalaklis & Fabio Ballini, Cham, Switzerland: Springer, 2018, p. 157-168Chapter in book (Refereed)
    Abstract [en]

    The vast majority of ships trafficking the oceans are fuelled by residual oil with high content of sulphur, which produces sulphur oxides (SOx) when combusted. Additionally, the high pressures and temperatures in modern diesel engines also produce nitrogen oxides (NOx). These emissions are both a hazard to health and the local environment, and regulations enforced by the International Maritime Organization (IMO) are driving the maritime sector towards the use of either distillate fuels containing less sulphur, or the use of exhaust gas cleaning devices.TwocommontechniquesforremovingSOx andlimitingNOx aretheopen loop wet scrubber and exhaust gas recirculation (EGR). A scrubber and EGR installation reduces the overall efficiency of the system as it needs significant pumping power, which means that the exhaust gases are cleaner but at the expense of higher CO2 emissions. In this paper we propose a method to integrate an exhaust gas cleaning device for both NOx and SOx with an organic Rankine cycle for waste heat recovery, thereby enhancing the system efficiency. We investigate three ORC configurations, integrated with the energy flows from both an existing state-of-the-art EGR system and an additional open loop wet scrubber.

  • 10.
    Ahlgren, Fredrik
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Österman, Cecilia
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    A social sustainability perspective on an environmental intervention to reduce ship emissions2015In: Creating Sustainable Work-environments: Proceedings of NES2015, Nordic Ergonomics Society 47th Annual Conference, 01-04 November 2015, Lillehammer, Norway / [ed] Knut Inge Fostervold, Svein Åge Kjøs Johnsen, Leif Rydstedt, Reidulf G. Watten, 2015, p. A4-12-A4-15Conference paper (Refereed)
    Abstract [en]

    This paper reports a case study examining the effects on the shipboard work environment of an operative decision to change fuel oil type on two Swedish passenger vessels operating in the Baltic Sea. The results show positive changes in work tasks, reduced exposure to harmful pollutants evaporating from the fuel, reduced use of chemicals for cleaning, and a generally cleaner work environment. The outcome illustrates the benefit of a systems perspective when evaluating environmental interventions. Here, the intervention can be seen as an investment that not only reduces emissions to the environment, but contributes towards sustainable working life at sea.

  • 11.
    Ahlin, Jane
    et al.
    Swedish Ergonomics and Human Factors Society, Sweden.
    Österman, Cecilia
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Osvalder, Anna-Lisa
    Chalmers University of technology, Sweden.
    Hemphälä, Hilevi
    Lund University, Sweden.
    Glimne, Susanne
    Karolinska Insitutet, Sweden.
    Hägg, Göran M
    KTH Royal Institute of Technology, Sweden.
    Janzon, Olle
    SSAB Europe, Occupational Health & Safety.
    Pettersson, Per Johan
    Merident Optergo AB.
    Stavervik, Mathias
    Ericsson AB, Sweden.
    Strategies to develop and strengthen human factors and ergonomics knowledge among stakeholders in Sweden2015In: Proceedings 19th Triennial Congress of the IEA, Melbourne 9-14 August 2015, Melbourne: International Ergonomics Association , 2015Conference paper (Refereed)
    Abstract [en]

    Knowledge and application of human factors and ergonomics (HFE) has significant potential as auseful tool and solution provider in the development, design and implementation of safe, efficient and sustainable artefacts and systems. Yet, it seems that this HFE knowledge is not utilised to its full potential. In a world of competing financial and commercial priorities, HFE specialists have apparently not succeeded in selling the systems approach as a tool towards improved overall systems performance and human well-being.

    The present paper describes the strategic and practical workperformed by the Swedish Ergonomics and Human Factors Society (EHSS) to strengthen the quality of human factors and ergonomics knowledge and practice among various stakeholders in Sweden. EHSS view human factors and ergonomics as a systems and design oriented discipline that extends across all aspects of human activity. Beyond the traditional domains of specialization within the discipline, the physical, cognitive and organisational ergonomics, EHSS has identified three focus areas; visual ergonomics, voice ergonomics and ergonomics design for all.

    Practitioner Summary: This paper presents the strategic and practical work performed by the Swedish Ergonomics and Human Factors Society (EHSS) in order to strengthen the quality of human factors and ergonomics knowledge and practice in Sweden. EHSS has identified three focus areas for its strategic work: visual ergonomics, voice ergonomics and ergonomics design for all.

  • 12.
    Ahlin, Kjell
    et al.
    Saven EduTech AB.
    Brandt, Anders
    Saven EduTech AB.
    A smart way to analyze dynamic data2003In: Sound & vibration, ISSN 1541-0161, no February, p. 20-22Article in journal (Other academic)
    Abstract [en]

    In recent years MATLAB® has become a common software tool for general computational mathematics, in universities as well as in industry. In the field of noise and vibration analysis, MATLAB is very common in universities, but perhaps a little less common in the industrial world. In this article some ideas are presented on how MATLAB can be successfully used for analyzing experimental noise and vibration data. Through the introduction of toolboxes in this field, the less experienced user can take advantage of the powerful functionality of MATLAB, either as the main tool or as a complement to the many excellent menu driven systems available on the market. Some of the advantages and disadvantages of using MATLAB versus menu driven systems are also discussed.

  • 13.
    Ahlin, Kjell
    et al.
    Blekinge Institute of Technology.
    Brandt, Anders
    Axiom EduTech AB.
    Lagö, Thomas
    A New MATLAB Toolbox for Simulation and Parameter Identification of Nonlinear Mechanical Systems2007In: IMAC-XXV: A Conference & Exposition on Structural Dynamics, February 19 – 22, 2007, Orlando, Florida USA, 2007Conference paper (Refereed)
  • 14.
    Ahlin, Kristofer
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Absorptionskylmaskiner ombord: En undersökning om absorptionsprocessens potential ombord fartyg2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med denna undersökning är att teoretiskt undersöka den vatten/litiumbromidbaserade absorptionsprocessens potential ombord fartyg då processen enbart drivs av huvudmaskinens högtemperaturkylvatten. Undersökningen genomförs teoretiskt mot tre olika fartyg samt Sjöfartshögskolan i Kalmars maskinrumssimulator. För vardera fartyg undersöks driftenergikällan och kylbehovet ombord. Med det som underlag dras en slutsats om den vatten/ litiumbromidbaserade absorptionsprocessens potential ombord fartyget. Fartygens resultat ligger till grund för slutsatsen. Undersökningen visade att det finns potential för tekniken ombord undersökta fartyg.

  • 15.
    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.

  • 16.
    Ahmad, Waqar
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Sultan Qaboos Univ, Oman.
    Vakilinejad, Ali
    Sultan Qaboos Univ, Oman;Univ Tehran, Iran.
    Aman, Zachary M.
    Univ Western Australia, Australia.
    Vakili-Nezhaad, G. Reza
    Sultan Qaboos Univ, Oman.
    Thermophysical Study of Binary Systems of tert-Amyl Methyl Ether with n-Hexane and m-Xylene2019In: Journal of Chemical and Engineering Data, ISSN 0021-9568, E-ISSN 1520-5134, Vol. 64, no 2, p. 459-470Article in journal (Refereed)
    Abstract [en]

    This work presents the experimentally determined density (rho), viscosity (eta), speed of sound (u), and surface tension (sigma) data for tert-amyl methyl ether (TAME) + n-hexane and TAME + m-xylene systems at several temperatures (298.15, 308.15, 318.15, 323.15, and 328.15 K). These experimentally determined thermophysical data are utilized to compute various excess/deviation parameters such as molar volume (V-E), isentropic compressibility (K-s(E)), speed of sound (u(E)), deviation in viscosity (Delta In eta), isobaric thermal expansion coefficient (alpha(E)(P)), and surface tension (sigma(E)). The inspection of parameters response may interpret the existing specific molecular interactions as well as the mixing behavior of solutions. The critical analysis of observed parametric behavior have unveiled the strong and weak molecular interactions in TAME with m-xylene and TAME with n-hexane systems, respectively.

  • 17.
    Ahmed, Suhail
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Sun, Hong
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Developing a Model for Managing Production Performance of Small and Medium Enterprises in Sweden2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The study developed a model for production performance management of small and medium enterprises (SMEs) in Sweden. The developed model works for assessing, follow up and improvement in production performance. SMEs differ in size, structure, culture, competition, management practices, resource availability and lot more when compared with large organizations. SMEs also lack in effective performance management framework as most of the framework developed are designed for large organizations.

     

    Production is core and critical value adding process especially for SMEs manufacturer for their survival and growth. SMEs are more motivated with doing rather than measuring it. Taking all these consideration a comprehensive model is developed which consists of four major steps. The model starts with studying of company’s strategy, and then there are steps for design of production performance measurement which works for identifying details strategically aligned performance measures. Benchmarking step is included to compare performance with best practices, finally measurements results are analysed and improvement actions are taken to continuously improve the production performance.

     

    Developed model based on literature study, multiple case study (three case studies) are being conducted to check model applicability. The result of case studies supports the applicability and formulated problem is also well-answered by developed model.

  • 18.
    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.

  • 19.
    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.

  • 20.
    Alajbegovic, Faruk
    et al.
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Imsirovic, Alen
    Linnaeus University, Faculty of Technology, Department of Building and Energy Technology.
    Uppföljning av energiprestanda samt boendes upplevelser av Portvakten Söder: Energy Monitoring and residents' perceptions of Portvakten Söder2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Portvakten Söder i Växjö, med sina två huskroppar och 64 lägenheter är de högsta passivhusen i Sverige med en trästomme. En energiuppföljning görs för år 2012. Skillnader kring projekterat och uppmätt värde behandlas och klargörs. Granskning av funktionalitet och värmeåtervinningsmängd av avloppsvärmeväxlaren utreds. Ett frågeformulär har skickats ut och sammanställts, där hyresgästerna delar med sig av sina upplevelser utav Portvakten Söder.

  • 21. Albertazz, S.
    et al.
    Basile, F.
    Brandin, Jan
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Einvall, Jessica
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Fornasar, G.
    Hulteberg, C.
    Sanati, M.
    Trifir, F.
    Vaccari, A.
    Pt/Rh/MgAl(O) Catalyst for the Upgrading of Biomass-Generated synthesis gases.2009In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 23, no 1, p. 573-579Article in journal (Refereed)
  • 22. Albertazzi, Simone
    et al.
    Basile, Francesco
    Barbera, Davide
    Benito, Patricia
    Brandin, Jan
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Einvall, Jessica
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Fornasari, Giuseppe
    Trifirò, Ferruccio
    Vaccari, Angelo
    Deactivation of a Ni-Based Reforming Catalyst During the Upgrading of the Producer Gas, from Simulated to Real Conditions2011In: Topics in catalysis, ISSN 1022-5528, E-ISSN 1572-9028, Vol. 54, no 10, p. 746-754Article in journal (Refereed)
    Abstract [en]

    The deactivation of a nickel reforming catalyst during the upgrading of the producer gas obtained by gasification of lignocellulosic biomass was studied. The research involved several steps: the selective deactivation of the catalyst in a laboratory scale; the streaming of the catalyst with the producer gas of a downdraft and an oxygen/steam circulating fluidized bed (CFB) gasifier; and tests in a reformer placed in a slipstream of the CFB gasifier. The information obtained allowed to elucidate the catalyst deactivation mechanisms taking place during the reforming of the producer gas: physical deactivation by deposition of fine ashes, aerosol particulate or carbon; poisoning by H2S and HCl present in the gas phase and thermal sintering because of the high operation temperatures required to avoid the chemical deactivation. These physical and chemical effects depended on the composition of the biomass fuel.

  • 23.
    Albertsson, Robin
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Hermansson, Joakim
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    LNG träningsmanual för M/T Bit Viking2013Independent thesis Basic level (university diploma), 10 HE creditsStudent thesis
    Abstract [sv]

    Denna uppsats är gjord på uppdrag av Tarbit Shipping som år 2011 konverterade sin tankbåt M/T Bit Viking från konventionell drift på tjockolja till LNG (Liquefied Natural Gas).Uppdraget som gavs var att upprätta en tränings manual till fartyget då det är ett krav från IMO (International Maritime Organization). Manualen skrevs i 3 st huvuddelar Kategori A, B och C. Kategori A är till för att manskap ombord ska få en kännedom om gasen och säkerhet runt den, Kategori B är skriven till däcksbefäl där det krävs en större kännedom om gasen och Kategori C är till för maskinbefäl. Manualen finns nu ombord på fartyget och på rederi kontoret för utbildning av nypåmönstrad personal och fortlöpande utbildning av ordinarie personal. Manualen är ett resultat på tolkning av IMO´s IGF kod (ANNEX11. RESOLUTION MSC.285(86)) där det står riktlinjer för säkerheten ombord på fartyg med maskiner som drivs på naturgas.

  • 24.
    Alegrim, Georg
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Anaje, Alexander
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Värmeåtervinning av luft i kycklingstallar: Återanvändning av energin i frånluften för luftförvärmning2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The consumption of chicken per inhabitant have increased in Sweden the last couple of years and today 23,2 kg is consumed per inhabitant and year. Because of this rise of Swedish chicken consumption, the awareness of investing in climate-smart alternatives have increased by the companies. The companies are decreasing the energy required during production, which ultimately leads to a reduced heating cost.

    The animal stall is heated by a boiler where water-based heating elements are providing the animal stall with heat along the walls. 

    It has been considered problematic to heat up the animal stall by reintroducing the air from inside the stall due to the fact that this air often is too dusty, which contributes to blockage of filters and ducts. There are a number of different heat exchangers that can handle this kind of dust and particles today. 

    Two different heat exchangers will be compared, a recuperative plate heat exchanger and a regenerative rotary heat exchanger.

    The animal stall must keep a low CO2 value and it is important to keep the chickens bedding dry by a low humidity inside the stall.

    The study shows that the total heat for one breeding round, which today is approximately 48,2MWh, which equals a saving by using an air heat exchanger of 24,8MWh. The result of the comparison of the two heat exchangers has shown that the regenerative (rotary) heat exchanger reintroduces moisture in the stall, which the recuperative (plate heat exchanger) does not. The follow up for this study was 34 days, from the chickens’ birth to the slaughter. During day 28-30 the animal stall becomes self-sufficient considering heat, which means that the heat exchanger could generate the heat required for the facility without the use of the stalls chip boiler.

    The study is implemented with a calculated volume flow due to a short outlet channel on the system, this can lead to a risk of a minor faulty value.

    Regard to the humidity in the stall, it is preferable to use a plate heat exchanger as the rotating heat exchanger precipitates water of 3 grams/kg of dry air.

  • 25.
    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.

  • 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.
    Al-Hamed, Heba
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Qiu, Xiaojin
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A Model for Assessing Cost Effectiveness of Applying Lean Tools2007Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to develop a model for assessing cost effectiveness of applying lean tools. The

    model consists of eight phases: it starts by understanding customers' requirements using Voice of Customer

    (VOC) and Quality Function Deployment (QFD) tools. In phase 2, the current state of plant is assessed

    using lean profile charts based on Balanced Scorecard (BSC) measures. In phase 3 and phase 4,

    identification of critical problem(s) and generating of improvement suggestion(s) are performed. Phase 5

    provide evaluation of the cost effectiveness of implementing the suggested lean methods based on life cycle

    cost analysis (LCCA) and phase 6 prefers the right alternative based on multiple criteria decision making

    (MCDM). In phase 7 the selected alternative is supposed to be implemented and finally the user should

    monitor and control the process to make sure that the improvement is going as planned. The model was

    verified successfully using a case study methodology at one Swedish sawmill called Södra Timber in

    Ramkvilla, one part of Södra group. Results obtained from the study showed that the production and human

    resources perspectives are the most critical problem areas that need to be improved. They got the lowest

    scores in the lean profile, 63% and 68%, respectively. Using value stream mapping (VSM) it was found that

    the non value added (NVA) ratios for the core and side products are 87.4% and 90.4%, respectively. Using

    the model, three improvement alternatives were suggested and evaluated using LCCA and MCDM.

    Consequently, implementing 5S got the highest score, second came redesigning the facility layout.

    However, it was estimated that 4.7 % of NVA for the side product would be reduced by redesigning the

    facility layout. The recommendations were suggested for the company to improve their performance. The

    novelty of the thesis is based on the fact that it addresses two main issues related to lean manufacturing:

    firstly, suggesting lean techniques based on assessment of lean profile that is based on BSC and QFD, and

    secondly assessing the cost effectiveness of the suggested lean methods based on LCCA and MCDM. This

    thesis provides a generalized model that enables the decision-maker to know and measure, holistically, the

    company performance with respect to customer requirements. This will enable the company to analyze the

    critical problems, suggest solutions, evaluate them and make a cost effective decision. Thus, the company

    can improve its competitiveness.

  • 29.
    Alinder, Gertrud
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Installation av VDR på Calmare Nyckel2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Through this exam work, a Voyage Data Recorder was installed on the Kalmar Maritime Academy’s school ship Calmare Nyckel. The purpose of the installation was to create a tool for the teachers when they are giving feedback on the students’ manoeuvring exercises with the school ship. This work was made in project form during the last year of the marine engineer programme and partly during the following three years. The result was an installation that records the information from the bridge equipment that was judged to be central to be able to correctly mirror the manoeuvring of the ship, and the possibility to replay this information.

  • 30.
    Alm, Alexander
    Linnaeus University, Faculty of Science and Engineering, Kalmar Maritime Academy.
    Kolkraft med CSS2012Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    ABSTRAKT

    Detta arbete om kolkraft med CCS syftar till att ge läsaren en lite djupare bild av hur avskiljning, transportering och lagring kan fungera vid ett koleldat kraftverk utrustat med koldioxidavskiljning.

    Vilka olika tekniska metoder som finns eller är under utveckling för de olika stegen i processen och hur dessa fungerar.

    Arbetet tar även upp historien bakom kolet som bränsle och hur utvecklingen av olika reningstekniker tog fart.

    Generella fördelar och nackdelar med CCS bollas fram o tillbaka miljömässiga aspekter med tekniken samt den ekonomiska lönsamheten undersöks.

    Arbetet avslutas med en överblick över en verklig pilotanläggning i Schwarzepumpe i Tyskland.

  • 31.
    Alm, Christoffer
    et al.
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Mehari, Amanuel
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Utveckling av hanteringsmaskin för IKEA-påsar2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det här examensarbete handlar om att ta fram en ny maskin, en hanteringsmaskin, till TEXO Application i Älmhult. Syftet med maskinen är att den ska vika IKEAs kundpåsar, hanteringsmaskinen ska användas på samtliga IKEA varuhus världen över. Utvecklingen av hanteringsmaskinen går från enkla skisser av flera koncept till val av koncept och utveckling en denna till en fullständig ritning som det sedan byggs en prototyp utfrån. Effektiviseringen bland samtliga varuhus beräknas att öka då denna lösning ger de anställda mer tid till annat arbete.

  • 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.

  • 33.
    Almert, Josef
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Ljung, David
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Frekvensomriktardrift av sjökylvattenpumpar: Ett underlag för konvertering från strypreglering2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been conducted in cooperation with the engine crew onboard theSwedish Maritime Administration's icebreakers. The purpose of this work is to highlightthe benefits of conversion from throttling control to frequency control, of the sea waterpumps on their icebreakers. This by means of a frequency converter.Energy efficiency is something that is prioritized on modern ships, where everything isbuilt and optimized to be as cost-effective as possible. Old ships do often have oldersystems that are inefficient from an energy point of view, as the technology at the timeof construction was limited. Today's technology is getting cheaper and cheaper, whichmakes more people willing to phase out the old inefficient systems with throttleregulation, against new frequency-controlled systems.The result was that after three to four years, it would be worth installing a drive. Thefuel costs for running two cooling water pumps with a 60% load drive will generate asaving of 16961 SEK in fuel consumption. Running the sea water pumps withfrequency drives will help reduce wear and tear on pump and pipe systems, it will alsogenerate a reduced CO2 emission, which is beneficial from an environmental point ofview.The conclusion was that it was profitable to install frequency converters, both from anenvironmental and cost point of view.

  • 34.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A computerized model for assessing the return on investment in maintenance: following up maintenance contribution in company profit2009In: Engineering asset lifecycle management: Proceedings of the World congress on engineering asset management (WCEM 2009), 28-30 september 2009 / [ed] Dimitris Kiritsis, Christos Emmanouilidis, Andy Koronios, and Joseph Mathew, Springer, 2009Conference paper (Refereed)
    Abstract [en]

    In order to reduce as much as possible the economic losses that are generated due to lack or inefficient maintenance, it is necessary to map, analyse and judge maintenance performance and act on deviations before it is too late. It is always necessary for a company to act for increasing profit and consequently enhance its competitiveness. In this paper, a software model (MainSave) has been developed for mapping, monitoring, analysis, following up and assessing the cost-effectiveness of maintenance (and maintenance investments). MainSave can be used for assessing savings and profit/losses due to maintenance performance, identify problem areas and primarily plan for new beneficial investments in maintenance. The module has been tested at Fiat/CRF in Italy. The major conclusion is; applying MainSave it would be possible to identify, assess and follow up maintenance contribution in company business.

  • 35.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A Maintenance Model for Identification, Quantification and Elimination of Losses in Companies Profitability: Application Examples2009In: Proceedings of the 22nd international congress on condition monitoring and diagnostic engineering management / [ed] Aitor. Arnaiz; Ana. Aranzabe; B. K. N. Rao, Eibar: Fundación Tekniker , 2009, , p. 35Conference paper (Other academic)
    Abstract [en]

    A production process includes several sub-processes, which may also be called working areas or disciplines that are responsible for performing the different tasks required to accomplish the mission of the process. It is crucial that the tasks performed in these sub-processes are synchronised with each other without unnecessary and uncontrollable gaps and overlapping, which in turn may lead to losses in production time and manpower. It is important to avoid a shortage of resources, unplanned stoppages and idle times that may arise due to the gaps. In this paper gaps are generated due to missing the tasks or inputs that are required because of deficiencies in planning, the lack of responsibilities or of knowledge and experience concerning these inputs. On the other hand, effective synchronising of production-different disciplines will enhance production process effectiveness as well as company profitability and competitiveness.

    The problem addressed in this paper is: How should maintenance be considered in conjunction with plant activities, such as production, quality and personnel competence, in order to easily and effectively identify and quantify company losses in profitability and competitiveness and consequently to eliminate underlying causes? In this paper the gaps and overlapping between maintenance, production, competence and quality are defined, identified and described through a technical analysis of the production sub-processes and their respective sub-organisations. The major result achieved in this study is the development of a new model (Maintenance Function Deployment (MFD)), for an easy and effective identification and quantification of company losses in profitability and competitiveness for cost-effective elimination of the root-causes. MFD can be applied through identifying:

    1. the requirements that are necessary to achieve and maintain company strategic goals,

    2. tools to maintain the condition of these requirements,

    3. activities for the effective utilisation of the tools above, and

    4. the factors required to support the integration of maintenance with plant business for enhancing production process effectiveness as well as company profitability and competitiveness.

    The structure of the quality house has been used as a platform for developing MFD model for effectively integrating maintenance with production, competence and quality. Two examples are conducted to demonstrate the possibility of applying the model and its potential for enhancing production processes profitably. The main conclusion is: applying MFD gives an enormous opportunity to continuously maintain the quality of the working areas under consideration, which makes MFD one of the company’s objective-driven tools for enhancing its profitability and competitiveness. Also, it implies the application of the PDCA cycle, which in turn improves the integration of relevant working areas cost-effectively and continuously.

  • 36.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A Maintenance Model for Indentification, Quantification and Elimination of Losses in Companies Profitability: An Application Example2009In: COMADEM 2009: June 9-11 2009, San Sebastian, Spain, Miramar Palace / [ed] Aitor Arnaiz, Ana Aranzabe, and Raj BKN Rao, Eibar, Spain: Fundaci n Tekniker , 2009, p. 45-53Conference paper (Refereed)
    Abstract [en]

    A production process includes several sub-processes (working areas) that are responsible for performing the different tasks required to accomplish the mission of the process. Thus, it is important to avoid a shortage of resources, unplanned stoppages and idle times that may arise. The problem addressed in this paper is: How should maintenance be considered in conjunction with plant activities, such as production, quality and personnel competence for easily and effectively identifying and quantifying company losses in profitability and eliminating underlying causes? In this paper, the interactions between major working areas have been introduced and discussed. The major result achieved in this study is the development of a new model (Maintenance Function Deployment (MFD)), for an easy and effective identification and quantification of company losses in profitability. Four matrixes have been used for developing MFD model for effectively integrating maintenance with production, competence and quality. An application example is conducted to demonstrate the possibility of applying the model and its potential for enhancing production processes profitably. The main conclusion is: applying MFD gives an enormous opportunity to continuously maintain the quality of the working areas under consideration, which makes MFD one of the company’s objective-driven tools for enhancing its profitability and competitiveness.

  • 37.
    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

  • 38.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A model to diagnose the deviation in the maintenance performance measures2006In: Engineering Asset Management, 2006, p. 87-93Conference paper (Refereed)
    Abstract [en]

    In order to achieve the strategic goals, the company should utilise an efficient data gathering and analysis system for mapping the technical and economic situation, following up the development and detecting technical and economic deviations at an early stage to plan and perform necessary maintenance actions on time. In many cases, measuring and following up the development of relevant and well selected technical and economic performance measures can be more applicable for mapping the situation and making cost-effective decisions compared with monitoring big mount of data. But, in many cases it demands a reliable technique for interpretation of the behaviour of these performance measures especially if they are not linearly interrelated and if some of them reflect a combination of technical and financial impact. The problem addressed in this paper is; how is it possible to enhance the ability of detecting significant deviations in the maintenance performance measures at an early stage and tracing their root causes by using data- and knowledge base and inference engine? The major result achieved in this paper is a model developed for interpreting the changes in the maintenance performance measures and tracing their basic causes, which is verified in an example with typical data. The model consists of five modules; what performance measures to chose, how and why an eventual deviation on the performance measures occur, what to do to eliminate and prevent their reoccurrence and mapping of the current situation technically and financially. The main conclusion is that applying the model would enhance the ability of detecting changes in the maintenance performance through identifying the causes for elimination. In Al-Najjar et al (2004), a model for how to identify the measurable variables, which are needed to develop measures for monitoring maintenance performance behaviour systematically, is introduced and discussed. Also, five maintenance performance measures are propos

  • 39.
    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.

  • 40.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    An approach for the Selection of the most Cost- Effective Vibration Replacement Level1998Report (Other academic)
  • 41.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Assessment of the probability of failure of a rolling element bearing and its residual life in paper mills2000Report (Other academic)
  • 42.
    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.

  • 43.
    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.

  • 44.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Computerised Maintenance Decision Support System (MDSS) for Simulating and Selecting the most Cost-effective Production and Maintenance Solution: Case Study in FIAT/CRF, Italy2010In: Computerised Maintenance Decision Support System (MDSS) for Simulating and Selecting the most Cost-effective Production and Maintenance Solution: Case Study in FIAT/CRF, Italy / [ed] Susumu Okumura, Tadao Kawai, Peng Chen and Raj B.K. N. Rao, Hikone, Japan: Sunrise Publishing Limited , 2010, p. 8-Conference paper (Refereed)
    Abstract [en]

    To survive the hard international competition, it is necessary for many companies to enhance their competition positions through, for example; reducing production cost, and maintaining and improving production process and product quality for increasing the profit margin. In order to achieve these strategic goals, a tool for making investments in maintenance more profitable is developed, introduced, tested and discussed. This tool/module is one of the modules included by an innovatively new Maintenance Decision Support System (MDSS). Theoretical backgrounds are introduced, and software prototype (AltSim) for making the application of any of the tool on the daily basis easier and more cost-effective are developed, discussed and their functionalities are tested in FIAT/CRF, Italy. It is designed to support maintenance and production engineers to achieve cost-effective maintenance decisions. The major result of this study is development and testing of innovatively new tool/software module for simulating and selecting the most cost-effective production and maintenance solution. The major conclusion that can be drawn is; applying AltSim it is possible to identify and select the most cost-effective solution when there are several technically application solutions for the same problem.

  • 45.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Continuous reduction in LCC when using integrated vibration-based maintenance: a casestudy2000Report (Other academic)
  • 46.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Cost-eefective & continous improvement of production process and company's business when using Total Quality Maintenance (TQMain)2006In: Proceedings of the First International Conference on Maintenance Engineering, 2006, , p. 1-13p. 1-13Chapter in book (Refereed)
    Abstract [en]

    A new concept of condition-based maintenance (CBM), Total Quality Maintenance (TQMain) is presented. It aims to maintain not only machines but the quality of the essential elements involved in the production process, such as methods, operational conditions, personnel competence, raw material, quality and managerial systems. The major results achieved, which are based on several case studies, are: Evidence of prolonging the bearing's effective live by using more accurate diagnosis is confirmed when faulty bearing installation, faulty machinery design and harsh environmental condition are considered.

    Machine speed and load influence the information delivered by vibration signals. Applying vibration spectral analysis, it is possible to detect the deviations in the quality of a product during the processing time and before it is completed

    Maintenance profit of one paper machine was found to be at minimum about 3.58 MSEK yearly. The main conclusion is; identifying and eliminating causes behind deviations in quality and equipment condition at an early stage are vital to accomplish continuous improvements and to assure longer machine live and high quality products at competitive price

  • 47.
    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.

  • 48.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Dymanite: ett beslutsstödsystem för effektivare underhållsåtgärder, del III2010In: Bättre produktivitet, ISSN 1402-1145, no 6, p. 24-25Article in journal (Other (popular science, discussion, etc.))
  • 49.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Dynamic e-Maintenance: Applying eMaintenance Decision Support System (eMDSS) in Case Companies2011In: 7th IMA International Conference on Modelling in Industrial Maintenance and Reliability: Sidney Susses College, University of Cambrige, UK, UK: Institute of Mathematics & its applications , 2011Conference paper (Refereed)
    Abstract [en]

    In order to maintain and improve company profitability especially during financial crises and lower profit-margin, it is necessary to reduce economic losses. This can be achieved through maintaining and improving the quality of the elements involved in the production process. Therefore, the maintenance strategy applied should be dynamic to suit the changes occur in a production process cost-effectively. Therefore, it is essential for maintenance and production managers to have a system providing the data required to achieve dynamic and cost-effective maintenance decisions. In this paper, a new Maintenance Decision Support System (eMDSS) for achieving dynamic and cost-effective maintenance decisions is introduced, tested and discussed. It consists of three toolsets and five software modules for performing six services to; enhance accuracy of maintenance decisions, select the most cost-effective maintenance solutions, identify and prioritise problem areas, and assess losses in production time, and map, follow up and assess maintenance cost-effectiveness (maintenance savings and profit) to achieve continuous & cost effective improvement. The major result of this tsudy is verfication of a new innovative Mainteance Decision Support System (eMDSS). The system has been tested at Fiat (car manufacturer)/CRF in Italy and GORATU (CNC-machine manufacturer).  The main conclusion is; applying eMDSS it is possible to map production and maintenance processes, identify and prioritise problems, select the most cost-effective maintenance investment and follow up and control investments results.

  • 50.
    Al-Najjar, Basim
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Dynamite: ett beslutsstödsystem för effektivare underhållsåtgärd, del II2010In: Bättre produktivitet, ISSN 1402-1145, no 3, p. 24-25Article in journal (Other (popular science, discussion, etc.))
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