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  • 201.
    Almgren White, Anette
    Växjö universitet, Fakulteten för humaniora och samhällsvetenskap, Institutionen för humaniora. Litteraturvetenskap.
    Uppsatshandledning i praktiken2007Inngår i: Uppsatshandledning -tankar från forskningscirklar: Uppsatshandledning i praktiken, Växjö University Press , 2007, s. 33-40Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 202.
    Almgren, Zara
    et al.
    Växjö universitet, Fakulteten för humaniora och samhällsvetenskap, Institutionen för vårdvetenskap och socialt arbete.
    Karlsson, Lisa
    Växjö universitet, Fakulteten för humaniora och samhällsvetenskap, Institutionen för vårdvetenskap och socialt arbete.
    JAG SKAR MIG FÖR ATT ORKA FINNAS TILL: - En litteraturstudie utifrån självbiografier om självskadande unga kvinnors upplevelser av lidande och välbefinnande2009Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Bakgrund: Självskadebeteende hos unga kvinnor är ett fenomen som har blivit allt vanligare under de senaste åren. Dessa patienter söker sig till alla delar av vården, vilket gör att det som sjuksköterska är viktigt att kunna bemöta dem på bästa sätt. Syfte: Syftet var att utifrån självbiografier beskriva självskadande unga kvinnors upplevelser av lidande och välbefinnande. Metod: Vi använde oss av en kvalitativ innehållsanalys, där vi utgick från fem självbiografier. Resultat: Resultatet visar på två huvuddrag som kännetecknar de unga kvinnornas upplevelser av ohälsa och hälsa. Dessa är relationen till de närstående, om denna var god kände de sig tillfreds. Det andra huvuddraget var att makt/vanmakt påverkade dem negativt när vårdpersonalen tog makten.Slutsats: Närståendes betydelse för de unga kvinnornas upplevelse av lidande och välbefinnande är viktigt därför bör ökat stöd till närstående prioriteras i vården. Vidare bör vårdpersonalen använda sin makt till att lindra de unga kvinnornas sjukdomslidande istället för att åsamka ett vårdlidande.

  • 203.
    Almqvist, Therése
    et al.
    Växjö universitet, Fakulteten för humaniora och samhällsvetenskap, Institutionen för vårdvetenskap och socialt arbete.
    Pohlman, Mari
    Växjö universitet, Fakulteten för humaniora och samhällsvetenskap, Institutionen för vårdvetenskap och socialt arbete.
    Strategier för en gräsrotsbyråkrat: en intervjustudie av biståndshandläggning i äldreomsorgen2009Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    In our paper we chose to study care management in the old age care. According to the law for the social services the needs of elderly should govern the assistance they are granted. But research has shown that municipal guidelines govern the assistance and that the elderly have to adjust their needs to them. Thus there is a discrepancy between law and practice. The aim of this study was to understand how care managers relate to municipal guidelines, laws and the requests of elderly when the application for assistance is established. We wanted to understand what strategies they use to deal with situations when the aforementioned factors are not consistent. The theoretical approaches we chose were Lipsky’s theory of street-level bureaucrats. The method we used was qualitative and consisted of six informal interviews made with care managers in the municipality of Växjö, Sweden. Based on our interviews we identified eight different themes: the availability of resources, directing conversations and the use of routines, legitimize decisions, legitimize through the possibility of entering an appeal, legitimize through constructing the client, the adaptation of the objectives to the possibilities to perform them, diminishing their capability and professionalism. Our conclusion was that the requests of elderly did govern their assistance, as long as they coincided with the municipal guidelines. If the requests fell outside the guidelines it often required medical or social reasons for granting them. The municipal guidelines were never abandoned to create a uniquely designed assistance.

  • 204. Alm-Roijer, C
    et al.
    Fridlund, Bengt
    Växjö universitet, Fakulteten för humaniora och samhällsvetenskap, Institutionen för vårdvetenskap och socialt arbete.
    Stagmo, M
    Erhardt, L
    Knowing your risk factors for cononary heart disease improves adherence to advice on lifestyle changes and medication2006Inngår i: J Cardiovasc Nurs, Vol. 21Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 205.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    A computerized model for assessing the return on investment in maintenance: following up maintenance contribution in company profit2009Inngår i: 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, 2009Konferansepaper (Fagfellevurdert)
    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.

  • 206.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    A Concept for Detecting Quality Deviation Earlier than when using Traditional Diagram in Automotive: A Case study2001Inngår i: International Journal of Quality & Reliability Management, ISSN 0265-671X, E-ISSN 1758-6682, Vol. 18, nr 9, s. 917-940Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 207.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    A Maintenance Model for Identification, Quantification and Elimination of Losses in Companies Profitability: Application Examples2009Inngår i: 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, , s. 35Konferansepaper (Annet vitenskapelig)
    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.

  • 208.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    A Maintenance Model for Indentification, Quantification and Elimination of Losses in Companies Profitability: An Application Example2009Inngår i: 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, s. 45-53Konferansepaper (Fagfellevurdert)
    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.

  • 209.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och 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 finance2005Inngår i: Creation of Industrial Competitiveness: CIC 2001-2004 / [ed] Basim Al-Najjar ; Anders Pehrsson, Växjö: Växjö University Press , 2005, s. 29-38Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 210.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    A model that describes the impact of integrated vibration-based maintenance on company´s business2002Konferansepaper (Fagfellevurdert)
  • 211.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    A model to diagnose the deviation in the maintenance performance measures2006Inngår i: Engineering Asset Management, 2006, s. 87-93Konferansepaper (Fagfellevurdert)
    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

  • 212.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Matematiska och systemtekniska institutionen.
    Accuracy, effectiveness and improvement of Vibration-based Maintenance in Paper Mills: Case Studies2000Inngår i: Journal of Sound and Vibration, ISSN 0022-460X, E-ISSN 1095-8568, Vol. 229, nr 2, s. 389-410Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Many current vibration-based maintenance (VBM) policies for rolling element bearings do not use as much as possible of their useful lives. Evidence and indications to prolong the bearings’ mean effective lives by using more accurate diagnosis and prognosis are confirmed when faulty bearing installation, faulty machinery design, harsh environmental condition and when a bearing is replaced as soon as its vibration level exceeds the normal. Analysis of data from roller bearings at two paper mills suggests that longer bearing lives can be safely achieved by increasing the accuracy of the vibration data. This paper relates bearing failure modes to the observed vibration spectra and their development patterns over the bearings’ lives. A systematic approach, which describes the objectives and performance of studies in two Swedish paper mills, is presented. Explanations of the mechanisms behind some frequent modes of early failure and ways to avoid them are suggested. It is shown theoretically, and partly confirmed by the analysis of (unfortunately incomplete) data from two paper mills over many years, that accurate prediction of remaining bearing life requires: (a) enough vibration measurements, (b) numerate records of operating conditions, (c) better discrimination between frequencies in the spectrum and (d) correlation of (b) and (c). This is because life prediction depends on precise knowledge of primary, harmonic and side band frequency amplitudes and their development over time. Further, the available data, which are collected from relevant plant activities, can be utilised to perform cyclic improvements in diagnosis, prognosis, experience and economy.

  • 213.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    An approach for continuous reduction in LCC when using integrated vibration-based maintenance: A case study1999Inngår i: Proceedings COMADEM '99, 1999, s. 159-168Konferansepaper (Fagfellevurdert)
    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.

  • 214.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    An approach for the Selection of the most Cost- Effective Vibration Replacement Level1998Rapport (Annet vitenskapelig)
  • 215.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Assessment of the probability of failure of a rolling element bearing and its residual life in paper mills2000Rapport (Annet vitenskapelig)
  • 216.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Company´s business and competitiveness enhancement: A model of integrated vibration-based maintenance impact on company´s effectiveness2002Inngår i: Proceedings of COMADEM 2002: 15th International Congress on Condition Monitoring and Diagnostic Engineering Management, 2002, s. 238-248Konferansepaper (Fagfellevurdert)
  • 217.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Continuous reduction in LCC when using integrated vibration-based maintenance: a casestudy2000Rapport (Annet vitenskapelig)
  • 218.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Cost-eefective & continous improvement of production process and company's business when using Total Quality Maintenance (TQMain)2006Inngår i: Proceedings of the First International Conference on Maintenance Engineering, 2006, , s. 1-13s. 1-13Kapittel i bok, del av antologi (Fagfellevurdert)
    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

  • 219.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Criteria for the selection of a cost-effective maintenance policyManuskript (preprint) (Annet vitenskapelig)
  • 220.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Data coverage and quality, diagnosis and maintenance decision, and their economic impact on the company´s profits: case studies2002Inngår i: Proceedings of the 16th European Maintenance Congress : Euromaintenance 2002, 2002, s. 283-293Konferansepaper (Fagfellevurdert)
  • 221.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Establishing and running a condition-based maintenance policy: applied example of vibration-based maintenance2007Inngår i: Proceedings of WCEAM / CM2007, 2007, s. 106-115Konferansepaper (Fagfellevurdert)
    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.

  • 222.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Ett nytt underhållskoncept för kvalitetssäkring och förbättring till minskadekostnader: Totalt kvalitetsunderhåll (TKU)1999Rapport (Annet vitenskapelig)
  • 223.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Hur vet man om det är bättre att utveckla produktionen än att flytta ut den?2005Inngår i: Bättre produktivitet, ISSN 1402-1145, nr 8, s. 26-26Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 224.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Impact of integrated vibration-based maintenance on plant LCC: A case study2000Inngår i: Quality reliability and maintenance (QRM), 2000, s. 105-109Konferansepaper (Fagfellevurdert)
    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

  • 225.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Impact of real-time measurements of operating conditions on effectiveness and accuracy of vibration-based maintenance policy: A Case Study in Paper Mill2000Inngår i: Journal of Quality in Maintenance Engineering, ISSN 1355-2511, E-ISSN 1758-7832, Vol. 6, nr 4, s. 275-287Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 226.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Improvement in effectiveness of vibration-based condition monitoring system in paper millsManuskript (preprint) (Annet vitenskapelig)
  • 227.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Improvement in effectiveness of vibration-based monitoring systems1997Rapport (Annet vitenskapelig)
  • 228.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Maintaining performance-efficeincy and quality rate for high effectiveness of manufacturing machines1999Inngår i: Proceedings Condition Monitoring '99 / [ed] Jones, MH; Sleeman, DG, 1999, s. 343-358Konferansepaper (Fagfellevurdert)
    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

  • 229.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design. systemekonomi.
    Maintenance from Different Perspectives: Total Quality Maintenance (TQMain) for a Comprehensive Asset Maintenance2008Inngår i: ICOMS 2008 Conference Proceedings, Asset Management Council, Surrey Hills, Australia , 2008, s. 37/1-8Konferansepaper (Fagfellevurdert)
    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.

  • 230.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Maintenance from Different Relevant Perspectives: Total Quality Maintenance (TQMain) for a Comprehensive Asset Maintenance2008Konferansepaper (Fagfellevurdert)
  • 231.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Maintenance Function Deployment (MFD) for Cost-effective & Continuous Improvement of Company’s Business: Using Total Quality Maintenance (TQMain)2008Konferansepaper (Fagfellevurdert)
  • 232.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Maintenance or Maintenance Lack which Actually Costs: A Model to Quantify the Impact of VBM on Company's Business2005Inngår i: International conference on condition monitoring, 2005, s. 15-20Konferansepaper (Fagfellevurdert)
  • 233.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    On the design of the integration of quality, maintenance and production2003Inngår i: Condition monitoring and diagnostic engineering management; COMADEM 2003 / [ed] Shirivastav, O.P. ; A-Najjar B. ; Rao, R. B.K. N., 2003, s. 23-33Konferansepaper (Fagfellevurdert)
  • 234.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    On the effectiveness of vibration-based monitoring programsManuskript (preprint) (Annet vitenskapelig)
  • 235.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    On the Relation between Operating Conditions and Changes in Vibration Signature: A Case Study in Paper Mill1998Rapport (Annet vitenskapelig)
  • 236.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    On the relation between operating conditions and changes in vibration signature: A case study in paper mill machine1998Inngår i: International condition monitoring conference; 1998 technology showcase / [ed] Humphrey, G. R. ; Martin, R. W., 1998, s. 226-235Konferansepaper (Fagfellevurdert)
  • 237.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    On the selection of condition based maintenance for mechanical systems1991Inngår i: Operational reliability and systematic maintenance / [ed] Holmberg, K; Folkeson A., London: Elsevier Applied Science , 1991, s. 153-175Kapittel i bok, del av antologi (Fagfellevurdert)
    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).

  • 238.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Product quality problems can be detected earlier by vibration spectral analysis than by traditional quality control diagram: A case study2000Konferansepaper (Fagfellevurdert)
  • 239.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Project-based learning for technical education in master programms2006Inngår i: International quality in engineering education / [ed] Pudlowski, ZJ, 2006, s. 216-219Konferansepaper (Fagfellevurdert)
    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.

  • 240.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Selection and improvment of a cost-effective maintenance policy: the case of rolling element bearings1998Inngår i: International Journal of COMADEM, ISSN 1363-7681, Vol. 1, nr 2, s. 25-36Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 241.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och 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 Business2007Inngår i: International Journal of Production Economics, ISSN 0925-5273, E-ISSN 1873-7579, Vol. 107, nr 1, s. 260-273Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 242.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    The Vibration Level of Rolling Element Bearings in Paper Mill Machine1999Rapport (Annet vitenskapelig)
  • 243.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Total Quality Maintenance for Assuring Continuous Improvement of Company’s Profitability and Competitiveness: Case Studies2006Inngår i: Condition monitoring and diagnostic engineering management: COMADEM 2006 / [ed] Kumar, U. ; Parida, A ; Rao, R. B. K. N., Luleå universitet, Luleå , 2006, s. 181-190Konferansepaper (Fagfellevurdert)
    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

  • 244.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Total Quality maintenance (TQMAIN) a new concept for continuous enhancing of company's economic competitiveness: case studies2002Inngår i: Proceedings IFRIMmmm: maintenance mangament & modelling conference, Växjö, 2002Konferansepaper (Fagfellevurdert)
  • 245.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    TTT-plots for CM of rolling element bearings in paper mills2000Inngår i: Proceedings systems integrity and maintenance / [ed] Mathew, J; Zhong, B, 2000, s. 62-68Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In general, it is easier to detect that some sort of damage has occurred in rolling element bearings than to accurately assess damage severity and the risk of failure if no replacement is done when using vibration-based maintenance. When the vibration level of a rolling element bearing is increasing, close to or greater than the predetermined replacement level, the assessment of the probability of a bearing's failure enhances the decision making process. Thus, at each vibration measurement a decision has to be made regarding whether the bearing needs to be replaced and how urgent it is actually. The paper describes a graphical method for both assessing the probability of failure of damaged rolling element bearing and predicting the residual of its effective life. It uses history of the bearing in question and life statistics as well as the vibration levels at failure/condition-based replacements of past bearings of the same design or very similar performing and duties. This method is based on the concept of Total Time on Test, M-plot. The application of TTT-plot on age and condition-based maintenance techniques are discussed and two examples are presented. This graphical method is developed from previous work by the author and others.

  • 246.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Vibration monitoring of rolling element bearings in paper mills: Effectiveness and improvements1998Konferansepaper (Fagfellevurdert)
  • 247.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Vibration signal analysis as a quality assurance tool in manufacturing industry: A case study2000Inngår i: European maintenance congress; Euromaintenance 2000, 2000, s. 41-48Konferansepaper (Fagfellevurdert)
  • 248.
    Al-Najjar, Basim
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Vibration spectral analysis as a quality assurance tool: a case study2000Rapport (Annet vitenskapelig)
  • 249.
    Al-Najjar, Basim
    et al.
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Alsyou, Imad
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Mechanistic model for predicting the vibration level: A case study2004Inngår i: Proceedings of MIMAR 2004 - 5th IMA International Conference on Modelling in industrial maintenance and reliability: Impact on practice, 2004, s. 7-12Konferansepaper (Fagfellevurdert)
  • 250.
    Al-Najjar, Basim
    et al.
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Institutionen för teknik och design.
    Alsyouf, Imad
    Enhancing a Company’s Profitability and Competitiveness Using Integrated Vibration-Based Maintenance: A Case Study2004Inngår i: European Journal of Operational Research, ISSN 0377-2217, E-ISSN 1872-6860, Vol. 157, nr 3, s. 643-657Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper a model is developed for identifying, monitoring and improving the economic impact of vibration-based maintenance (VBM). This model provides an additional possibility of identifying where, why and how much capital should be invested, and judges whether or not the investment was cost-effective. The model is further utilised to develop relevant maintenance performance measures. When the model was tested in a Swedish paper mill, the main results were: the average yearly maintenance profit achieved using integrated VBM was at least 3.58 million Swedish kronor (SEK) (approximately USD 0.358 million), and average potential savings (economic losses) were around SEK 30 million (USD 3 million). Furthermore, the model facilitated identification of problem areas and recognition of where investments should be made. The major conclusion is that the better the data coverage and quality, the greater control is possible over direct maintenance costs, savings and further profits in maintenance. Moreover, using the model it would be easier and more reliable to detect deviations in the maintenance performance and eliminate their causes at an early stage.

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