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  • 1.
    Abrahamsson, Agneta
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Gesällbrevet hänger på håret: Sex gymnasieelevers uppfattningar om gesällbrevet på frisörprogrammet2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose with this lucubration is to investigate hairstylist student’s apprehension about the apprentice diploma. The apprentice diploma is an occupation verification indicating on the hairstylist’s knowledge and competence, and it is the only verification in the business that you can use in order to measure the students knowledge. Three students out of thirty, in year 2009, chose to graduate with an apprentice diploma. Based on these figures I am to investigate six graduating students opinion using qualitative interviews. Another quest is to inform and gain interest about the apprentice diploma.  The result demonstrate what earlier research already shows, amongst other things, that the students no longer have the practical knowledge needed in order to come to a worksite and therefore find it difficult to work as an apprentice. The business expects the students to be self-driven and dissatisfaction from the school and the business increases. Is the occupation as a hairstylist about to loose its profession or are you allowed to call yourself a professional without a proper diploma?

     

  • 2.
    Ackerot, Magnus
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Rask, Joakim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Varför bli yrkeslärare?: Vilka uppfattningar har yrkeslärare om den motivation, som behövs för att studera till yrkeslärare?2009Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna undersökning är att med bakgrund av att yrkeslärare inom gymnasieskolan beskrivs som en bristvara, och med tanke på det framtida behovet då bristen på yrkeslärare kommer att öka. Det vi vill belysa är vad som är motivationen och drivkraften för den enskilde individen i att bli yrkeslärare och även vilka drivkrafter som kan få obehöriga lärare att vilja bli behörig. Studien genomfördes med en kvalitativ ansats. Ett klusterurval gjordes var efter intervjuer genomfördes. Empiriska undersökningen gick ut på att med en halvstrukturerad intervjuguide intervjua ett antal olika personer. I dataanalysen användes Burnards (1991) 5 steg i den så kallade innehållsanalysen, vilket skapade olika teman. Resultatet efter vår undersökning, att den motivation och de drivkrafter som behövs för bli yrkeslärare eller att börja studera för att bli behörig yrkeslärare, är att man skall försöka lyfta fram de positiva sidorna med yrket och det givande mötet med ungdomarna i samhällsdebatten och media. Det är ett fantastiskt trevligt jobb. Att lönen och statusen kan bli bättre samt att det bör vara lättare för den som har goda yrkeskunskaper att komma in på en yrkeslärarutbildning. Oavsett längd på utbildningen så behövs det ett batteri av hjälp och stöd för att man skall klara av utbildningen samtidigt som man kanske både har familj och arbete.

     

  • 3.
    Afshari, Mazdak
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Östberg, Lina
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Helautomatisk växling av svetspistoler med en industrirobot2008Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The paper describes a final thesis carried out on assignment of Motoman Robotics Europe AB in Torsås, Sweden. The assignment was to find a solution for a fully automated switching of welding-guns with a Motoman HP-20 industrial robot. The project has formerly been a development-work with focus on a functioning practical solution. The work has proceeded in close cooperation and guidance from constructors at the company as well as support from our teacher. The result has given us a compact and ecstatically pleasing construction that fulfils the demands that the commissioner has ordered.

  • 4.
    Al Jaafar, Jaafar
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Projektering av platsbyggd villa2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract (in English)

    "This thesis work is a design project of an on-site construcktions. The issue addressed by the project was how to

    devise and design an detached house

    I have examined which architecture-drawings, construcktion-drawings and static calculations are needed to

    produce an on-site construcktions detached house.

    The result is presented in the finished drawings for the construction documents, which show a one-storey

    detached house with an attractive/accessible construction plan. It uses the combination of a strong style of

    architecture and a clear influence of functional design. This is clarified by the bench ceilings, and the facade,

    which is partly laying panel, partly white trimmed.

    Size: 153 square meters

    Number of rooms: 6, where of 3 are bedrooms."

  • 5.
    Al Jaafar, Jaafar
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Projektering av platsbyggd villa2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract (in English)

    "This thesis work is a design project of an on-site construcktions. The issue addressed by the project was how to

    devise and design an detached house

    I have examined which architecture-drawings, construcktion-drawings and static calculations are needed to

    produce an on-site construcktions detached house.

    The result is presented in the finished drawings for the construction documents, which show a one-storey

    detached house with an attractive/accessible construction plan. It uses the combination of a strong style of

    architecture and a clear influence of functional design. This is clarified by the bench ceilings, and the facade,

    which is partly laying panel, partly white trimmed.

    Size: 153 square meters

    Number of rooms: 6, where of 3 are bedrooms."

  • 6.
    Al-Ansari, Nabil
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Te Seng, Meng
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Studentbostäder i trä med Prefab-teknik2009Independent thesis Basic level (degree of Bachelor), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    The Results of this thesis was the creation of two designed house variants with a module to

    all the apartments. In addition till the first module there are three other modules of

    apartments that can be put in the houses if it so needs. The house are volume prefabricated

    and are placed on site in a way that it create an enclosure of the area which faces against the

    nature and car parks also lies hidden behind these houses.

    For the actual structure, a cross beam was created to carry the floor above and it is support

    by all four walls. The structure between the first and the second floor has no "syll" but

    instead there are two differently alternative to linking the floors in order so that it will not

    move. The reason with this solution was that there will not be any subsidence when the

    forces from above are pressed down ward. The forces are instead directly down to the next

    timber frame system. This can happen when the real estate's owner might want to build

    more floors on the house than the present two floors house when there is no land to build

    and spaces are needed in the future.

  • 7. 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)
  • 8.
    Alexandersson, Andreas
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Uhr, Ronnie
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A Quality improvement model and its applications to increase quality on a manufacturing process2004Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Companies always try to decrease different losses and in that way increase their profits. By improving the internal quality will the company reduce waste, improve productivity and increase their sales, and thereby increase their profit. Quality is therefore important for the companies. To be able to improve the internal quality must the company locate where, when and how the problem occurs.

  • 9.
    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.

  • 10.
    Alhamed, 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 Tools - A case study2007Independent 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.

  • 11.
    Ali, Sharafat
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Jonson, Bo
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Nitrogen rich Ca/Sr-Si-O-N glasses crystallization2009Conference paper (Refereed)
  • 12.
    Alma, Ibrahimovic
    et al.
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Abdi, Abdulaziz
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Bestämning av oxidationstalen för koppar i glas2004Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    Our examination project was carried out at Glafo, the Glass Research Institute that provides glass research, development and education. Our goal with this work was to investigate a method to determine different oxidation states of copper in glasses. The task includes: manufacturing of glasses with different copper contents, determination of extinctions coefficient copper and determination of different concentrations of copper in the glasses.

  • 13.
    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.

  • 14.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A Concept for Detecting Quality Deviation Earlier than when using Traditional Diagram in Automotive: A Case study2001In: International Journal of Quality & Reliability Management, ISSN 0265-671X, E-ISSN 1758-6682, Vol. 18, no 9, p. 917-940Article in journal (Refereed)
    Abstract [en]

    The problem addressed in this paper is how to utilise the concept of total quality maintenance (TQMain) to develop an integrated VBM (vibration-based maintenance) for detecting deviations in the machine condition and product quality (technical specifications), before the machine starts manufacturing defective items. Concepts of TQMain and integrated VBM are discussed. A technical analysis is conducted to identify quality problem cause roots when manufacturing crankshafts in Volvo, Motor, Skövde, Sweden. A factorial experiment is conducted to assess the effect and significance of the suspected causes. Vibration measurements from 7 points are collected. 

    The major conclusion of this study is; when using an effective, e.g. on the basis of TQMain concept, integrated VBM, deviations in product quality can be detected at an earlier stage than that when using usual quality control diagrams. Manufacturing defective items can be reduced dramatically (or prevented) which will eliminate bad quality- related losses.

  • 15.
    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.

  • 16.
    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.

  • 17.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A model for the creation of industial competitiveness: the role of companies' internal effectiveness in the creation and improvment of their competitiveness: a model for integrating technology and finance2005In: Creation of Industrial Competitiveness: CIC 2001-2004 / [ed] Basim Al-Najjar ; Anders Pehrsson, Växjö: Växjö University Press , 2005, p. 29-38Chapter in book (Other academic)
  • 18.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    A model that describes the impact of integrated vibration-based maintenance on company´s business2002Conference paper (Refereed)
  • 19.
    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

  • 20.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    An approach for continuous reduction in LCC when using integrated vibration-based maintenance: A case study1999In: Proceedings COMADEM '99, 1999, p. 159-168Conference paper (Refereed)
    Abstract [en]

    The biggest thread confronts achieving and maintaining high equipment effectiveness can be stated as; whether the improved manufacturing processes capable of producing quality products at a competitive cost. The effect of a new vibration-based maintenance concept, called Total Quality Maintenance (TQMain), is introduced. It aims to make intensive use of the real-time data acquisition and analysis to detect causes behind product quality deviation and failures in machinery. Also, it makes possible to follow damage development at an early stage to increase machine mean effective life and improve company's economy. The effect of TQMain on LCC of machinery and a company's economy is discussed. A case study to reveal savings in maintenance cost, when a vibration-based policy is involved, is presented. Using TQMain, company's economy can be improved effectively through continuous improvement of the technical and economic effectiveness of production processes.

  • 21.
    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)
  • 22.
    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)
  • 23.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Company´s business and competitiveness enhancement: A model of integrated vibration-based maintenance impact on company´s effectiveness2002In: Proceedings of COMADEM 2002: 15th International Congress on Condition Monitoring and Diagnostic Engineering Management, 2002, p. 238-248Conference paper (Refereed)
  • 24.
    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)
  • 25.
    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

  • 26.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Criteria for the selection of a cost-effective maintenance policyManuscript (preprint) (Other academic)
  • 27.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Data coverage and quality, diagnosis and maintenance decision, and their economic impact on the company´s profits: case studies2002In: Proceedings of the 16th European Maintenance Congress : Euromaintenance 2002, 2002, p. 283-293Conference paper (Refereed)
  • 28.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Establishing and running a condition-based maintenance policy: applied example of vibration-based maintenance2007In: Proceedings of WCEAM / CM2007, 2007, p. 106-115Conference paper (Refereed)
    Abstract [en]

    Maintenance is not only for solving technical problems as many may consider. It as a matter of fact is for solving production related problems, such as technical, environmental, etc. cost-effectively. This is why the technical part of maintenance, e.g. focusing on developing condition monitoring (CM) technology is not always sufficient alone to achieve a cost-effective maintenance policy. Without the maintenance management part responsible of identifying problem areas, data acquisition, management and analysis, decision-making procedures, planning and performing maintenance tasks at high quality and cost-effectively, the output of using any CM system cannot be guaranteed to be beneficial. In this paper, Condition monitoring and condition-based maintenance is introduced and discussed with respect to the differences between them. Also, the procedures required for establishing and running a condition/vibration-based maintenance is introduced, motivated and discussed.

  • 29.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Ett nytt underhållskoncept för kvalitetssäkring och förbättring till minskadekostnader: Totalt kvalitetsunderhåll (TKU)1999Report (Other academic)
  • 30.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Hur vet man om det är bättre att utveckla produktionen än att flytta ut den?2005In: Bättre produktivitet, ISSN 1402-1145, no 8, p. 26-26Article in journal (Other (popular science, discussion, etc.))
  • 31.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Impact of integrated vibration-based maintenance on plant LCC: A case study2000In: Quality reliability and maintenance (QRM), 2000, p. 105-109Conference paper (Refereed)
    Abstract [en]

    The biggest thread confronts maintaining high equipment effectiveness is; whether the improved manufacturing processes capable of producing quality products at a competitive cost. The effect of a new vibration-based maintenance concept, Total Quality Maintenance (TQMain), is introduced It aims at making intensive use of real-time data acquisition and analysis to detect causes behind product quality deviation and failures in machinery at an early stage and to allow control of these deviations to improve technical and economic of process effectiveness continuously. The effect of TQMain on machine's LCC and a company's economy is discussed. A case study revealing savings in maintenance cost, when a vibration-based policy is involved is presented

  • 32.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Impact of real-time measurements of operating conditions on effectiveness and accuracy of vibration-based maintenance policy: A Case Study in Paper Mill2000In: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 6, no 4, p. 275-287Article in journal (Refereed)
    Abstract [en]

    Relevant and reliable data from the surroundings in addition to the vibration measurements are required to achieve effective diagnosis and prognosis when a vibration-based maintenance (VBM) policy is used.

    The main conclusion is that the variation in the machine load and speeds influences the amplitudes of rolling element bearing defect frequencies. Therefore, changes in the machine speed and load should be considered when interpreting vibration spectra. This will improve the effectiveness and accuracy of fault diagnosis and prediction of the time to maintenance action.

    The paper classifies stoppage times and highlights the reasons behind them. Also, it discusses the consequential economic losses incurred by unplanned stoppages. During the period covered by this study (fifty-eight days), the total stoppage time was about 76.6 days and caused appreciable economic losses of about 2,3 millions SEK.

  • 33.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Improvement in effectiveness of vibration-based condition monitoring system in paper millsManuscript (preprint) (Other academic)
  • 34.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Improvement in effectiveness of vibration-based monitoring systems1997Report (Other academic)
  • 35.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Maintaining performance-efficeincy and quality rate for high effectiveness of manufacturing machines1999In: Proceedings Condition Monitoring '99 / [ed] Jones, MH; Sleeman, DG, 1999, p. 343-358Conference paper (Refereed)
    Abstract [en]

    The main objective of manufacturing companies is to achieve increased productivity, high plant availability, high quality rate, and increased safety, at the most competitive cost. Data collected by only one condition monitoring parameter are, sometimes, insufficient to achieve effective assessment of the condition of a machine due to its limited ability to cover the required information and the inherent uncertainty in the acquired data. The problem addressed in this paper, is how to keep availability, quality, and productivity at high levels through utilizing a common database, i.e. integrating the database of condition-based maintenance system with the main plant IT-system, for an innovative expert system. It was found that most research is focused on tool and process monitoring, using various types of condition monitoring parameters, to predict tool wear and tool life. Intelligent manufacturing systems techniques, e.g. Expert System, Fuzzy Logic and Neural Networks, are being used to integrate and interpret data from multiple sensors. But less attention was devoted to the development of integrated condition monitoring systems, which enable the user to evaluate a multi-variant system based on the data collected from, e.g. maintenance, quality, production and accountancy. The major conclusion is that; using an innovated expert system, based on a common database having better data coverage and quality, and a continuously improved knowledge base with intelligent inference engine, one can enhance the reliability of data, certainty of decision making, remove the redundancy in the monitoring system, and allow the user to detect and eliminate reasons behind variations through effective diagnosis and prognosis. This leads to continuous improvement in quality, productivity and availability at a reduced cost, and improved effectiveness of the manufacturing system

  • 36.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design. systemekonomi.
    Maintenance from Different Perspectives: Total Quality Maintenance (TQMain) for a Comprehensive Asset Maintenance2008In: ICOMS 2008 Conference Proceedings, Asset Management Council, Surrey Hills, Australia , 2008, p. 37/1-8Conference paper (Refereed)
    Abstract [en]

    Due to the interactions between the working areas involved in a production process, such as operation, quality, management, working environment, LCC management and analysis and maintenance, problems in these working areas are usually complex. It is well-known that maintenance is influenced by and influences these working areas. Maintenance role can be described technically using; failures, downtime, availability, planned stoppages, etc. or economically using; direct cost of maintenance, maintenance cost to production cost, spare part cost, etc. In order to high light maintenance technical and economic role and quantify its impact on company profitability and competitiveness, it is necessary to cover all relevant working areas within plant where maintenance affect. Thus, maintenance should be considered from different perspectives due to its interplay with the working areas involved in the production process. In this paper, maintenance is recognised as a means for maintaining the quality of the working areas involved in a production process at a continuous reduced cost. Also, we introduce maintenance from different perspectives based on its role in company profitability and competitiveness. Further more, the paper give big attention to introduce and discuss Total Quality maintenance (TQMain) philosophy with respect to the maintenance broader definition. An industrial case highlights TQMain applicability & maintenance economic importance is also introduced.

  • 37.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Maintenance from Different Relevant Perspectives: Total Quality Maintenance (TQMain) for a Comprehensive Asset Maintenance2008Conference paper (Refereed)
  • 38.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Maintenance Function Deployment (MFD) for Cost-effective & Continuous Improvement of Company’s Business: Using Total Quality Maintenance (TQMain)2008Conference paper (Refereed)
  • 39.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Maintenance or Maintenance Lack which Actually Costs: A Model to Quantify the Impact of VBM on Company's Business2005In: International conference on condition monitoring, 2005, p. 15-20Conference paper (Refereed)
  • 40.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    On the design of the integration of quality, maintenance and production2003In: Condition monitoring and diagnostic engineering management; COMADEM 2003 / [ed] Shirivastav, O.P. ; A-Najjar B. ; Rao, R. B.K. N., 2003, p. 23-33Conference paper (Refereed)
  • 41.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    On the effectiveness of vibration-based monitoring programsManuscript (preprint) (Other academic)
  • 42.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    On the Relation between Operating Conditions and Changes in Vibration Signature: A Case Study in Paper Mill1998Report (Other academic)
  • 43.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    On the relation between operating conditions and changes in vibration signature: A case study in paper mill machine1998In: International condition monitoring conference; 1998 technology showcase / [ed] Humphrey, G. R. ; Martin, R. W., 1998, p. 226-235Conference paper (Refereed)
  • 44.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    On the selection of condition based maintenance for mechanical systems1991In: Operational reliability and systematic maintenance / [ed] Holmberg, K; Folkeson A., London: Elsevier Applied Science , 1991, p. 153-175Chapter in book (Refereed)
    Abstract [en]

    The requirements for increased plant productivity and safety, and reduced maintenance costs, have led to an increasing interest in methods for condition monitoring of mechanical systems.  In the literature on Reliability-Centred Maintenance, RCM, the selection of a maintenance technique is mainly carried out on the level of system failure modes. Also, distinguishing criteria such as the long run average cost per unit time are not modelled see for example, Nowlan et al. (1978). In this study, a summary of three papers, Al-Najjar (1990a, b& c), component failure causes and failure mechanisms are involved in the selection problem, and a long run average cost per unit time is modelled. In chapter 2, the identification of significant components is described. State-changes of a component are discussed in chapter 3. New classifications of failures, monitoring parameters and monitoring techniques are proposed in chapters 2 and 4, respectively. Data sampling and analysis are discussed in chapter 4. The cumulative sum chart is proposed as a technique to reduce the fluctuation in monitoring parameter value.   In chapter 5, the selection of a cost-effective policy is carried out based on economical and non-economical distinguishing criteria. Chapters 1 to 5 summarise Al-Najjar (1990a). Modelling of a condition dependent failure rate function is discussed in chapter 6, which the summary of Al-Najjar (1990b). Chapter 7 is addressed to the problem of selecting a cost-effective monitoring technique based on observational data. To carry out the selection, we suggest the use of a generalization of a method, related to the Total Time on Test, TTT-plot, introduced by Bergman (1977). Also, a graphical method to estimate the threshold level of a monitoring parameter when using a cost-effective technique is proposed, see also Al-Najjar (1990c).

  • 45.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Product quality problems can be detected earlier by vibration spectral analysis than by traditional quality control diagram: A case study2000Conference paper (Refereed)
  • 46.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Project-based learning for technical education in master programms2006In: International quality in engineering education / [ed] Pudlowski, ZJ, 2006, p. 216-219Conference paper (Refereed)
    Abstract [en]

    Project-based learning methodology has been applied in a technical education Master programmes over almost the last almost nine years. The major results that have been achieved are that the graduated students have acquired a wide range of knowledge, together with deeper theoretical and practical skills in specific topics, and the effective enhancement of their analysis skills and training in constructive opposition to the examination of the research work of other groups. The main conclusion is that the course final written examination is not the only reliable examination form for judging the understanding of students. Project-based learning methodology provides a continuous examination of the gradual understanding of students instead of a final written examination.

  • 47.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Selection and improvment of a cost-effective maintenance policy: the case of rolling element bearings1998In: International Journal of COMADEM, ISSN 1363-7681, Vol. 1, no 2, p. 25-36Article in journal (Refereed)
    Abstract [en]

    The main result reported in this paper is that the bearing’s mean effective life could be extended appreciably if an existing vibration-based maintenance policy is used effectively. A new maintenance approach was developed to overcome some of the limitations of TPM and RCM and is based on the Deming managerial feedback cycle. It is a methodology to sustain and improve technical and economic effectiveness of the essential manufacturing process elements. It is shown that by using vibration-based monitoring, (VBM), program in the frame of a common database for a plant IT-system, the causes behind quality deviations and failures can be identified and eliminated effectively and the company’s economics would be improved. Criteria to select the most cost-effective VBM program and the most cost-effective vibration-based maintenance policy are developed. It is shown, by two case studies, that improvements in VBM systems can be achieved by effective feedback of the results of failures, renewal condition and VBM history analysis. The contribution of this study is: The development of a sequential method for the selection and improvement of a cost-effective vibration-based maintenance policy. This methodology can be used to justify, on economic criteria, the use of VBM systems to indicate when rolling element bearings should be renewed.

  • 48.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    The Lack of Maintenance and not Maintenance which Costs: A Model to Describe and Quantify the Impact of Vibration-based Maintenance on Company's Business2007In: International Journal of Production Economics, ISSN 0925-5273, E-ISSN 1873-7579, Vol. 107, no 1, p. 260-273Article in journal (Refereed)
    Abstract [en]

    Maintenance is usually considered as a cost-centre or necessary evil, because (according to this aspect) it costs the company unnecessarily big budget, while it should be treated as a profit-generating centre. The problem addressed in this paper is that if maintenance is a profit contributor how does maintenance technical impact transfer to the plant other activities such as production, quality and tied up capital, and how can this effect ultimately influence company's profit and competitiveness?

    In this paper, we discuss maintenance role in maintaining the quality of the essential elements contribute in the manufacturing process such as production/operation and quality on the economic basis for achieving the competitive advantages desired. Interactions between maintenance, production and quality, and how simple technical effects of maintenance in the operative level can be transferred to the economic effect in the strategic level influencing company’s profitability and competitiveness is discussed. A model describes the mechanisms through which vibration-based maintenance (VBM) impact is transferred to the plant other activities and company's business is developed and verified using real and typical data based on the author’s experience in the Swedish paper mills.

    The main result of this study is developing a model for converting vibration-based maintenance technical to financial impact and assessing it. The model potential and applicability is tested using a combination of real and typical data. The result also demonstrates how the potential of the VBM impact on the production, quality, tied up capital and different relevant expenses can be assessed financially. Furthermore, the model can be utilised for two additional objectives; for examining whether the investment done in maintenance is cost-effective or not, and simulating maintenance financial impact on the relevant working areas in order to assess the investment required before selecting and applying the improvement plan. The major conclusions are; applying the model, VBM policy can be introduced as a profit centre, and identifying the transferring mechanisms of maintenance impact highlights where, why and how much should be invested in order to enhance production and maintenance performance continuously and cost-effectively.

  • 49.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    The Vibration Level of Rolling Element Bearings in Paper Mill Machine1999Report (Other academic)
  • 50.
    Al-Najjar, Basim
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Total Quality Maintenance for Assuring Continuous Improvement of Company’s Profitability and Competitiveness: Case Studies2006In: Condition monitoring and diagnostic engineering management: COMADEM 2006 / [ed] Kumar, U. ; Parida, A ; Rao, R. B. K. N., Luleå universitet, Luleå , 2006, p. 181-190Conference paper (Refereed)
    Abstract [en]

    Industries with intensive invested capital demands healthy processes continuously to achieve their economic goals, because any interruption of the production caused by any equipment malfunction or failure may result in a major disruption of output or even production shutdown. Thus, an effective maintenance concept should be evolved to provide the required tools, data and methods for detecting deviations at an early stage to maintain and enhance the availability of machinery, product quality and profits. 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 have achieved in this study are

    Evidence of prolonging the bearing's mean effective live by using more accurate diagnosis and prognosis are confirmed when faulty bearing installation, faulty machinery design and harsh environmental condition are considered.

    Changes in the 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. Several case studies have been conducted during the last ten years to verify the applicability and benefits of TQMain are discussed

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