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Öka kundnöjdheten - minska felaktiga leveranser : En fallstudie över leveranssäkerheten vid ABB Machines i VästeråsStrömberg, Evelina January 2018 (has links)
Leveranssäkerhet är en avgörande faktor för att tillgodose kunder och deras behov. Det handlar om att rätt produkt levereras i rätt förpackning i rätt tid efter kundens godkännande. ABB Machines i Västerås levererar växelströmsmaskiner till kunder i projektform. Projektformen skapar förutsättningar för stor kundanpassning vilket i sin tur ställer krav på flexibilitet och resurser som kan användas mångsidigt. Hanteringen av utleveransprocessens som ska färdigställa projekten genom att komplettera maskinerna med montage- och sidokollin anses inte vara optimal. Detta har lett till högre omkostnader och flertalet omarbeten för att kunna leverera och tillgodose kunderna och deras behov. Detta examensarbete inom kvalitetsutveckling på Luleå tekniska universitet genomförs med syfte att identifiera vilka faktorer som påverkar leveranssäkerheten och hur utleveransprocessen ska hanteras för att öka leveranssäkerheten. Huvudfokuset är att identifiera hur processen ska hanteras för att förenklas och säkerställas. För att nå dit utvärderas och analyseras utleveransprocessen utifrån de tre teoriområdena; standardisering, visualisering och kvalitetssäkring. Studien genomfördes som en fallstudie på ABB Machines i Västerås. Genom observationer och intervjuer samlas relevant data in för att skapa en bild över hur arbetet går till och vilka problem som uppkommer i processen. Detta för att skapa möjlighet till att identifiera områden med förbättringsmöjligheter. Resultat av studien visar att ABB Machines inte har använt sig av de tre fokusområdena standardisering, visualisering och kvalitetssäkring i lika stor omfattning som det finns möjligheter till. Inom flertalet områden i processen finns möjlighet till både utveckling av redn införda arbetssätt samt implementering av nya sätt att genomföra moment, sprida information samt kvalitetssäkra moment. Rekommendationerna har ett övergripande fokus där flera olika delar av utleveransprocessen behandlas. Rekommendationerna är uppdelade på kort-, medellång-, och långsikt. Denna fördelning genererar enklare rekommendationer som kan implementeras direkt samt rekommendationer med behov av anpassning för att på längre sikt kunna bidra till en förbättring i processen. Enligt den analys som har genomförts av utleveransprocessen är slutsatsen att ABB Machines har möjligheter att förenkla och effektivisera moment i flödet. Det kommer också generera möjligheter till att på ett enklare sätt kunna säkerställa leveranserna till slutkund.
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Säkerställning av mätprocessers tillförlitlighet : En fallstudie på Volvo Group Trucks Operations / Ensuring the reliability of measurement processLjung, Marcus, Staf Vadin, Adam January 2018 (has links)
Quality insurance is an important part of a manufacturing company in order to achieve and maintain its competitiveness. To measure how the company’s processes are performing, it is necessary to have reliable measurement data. Reliability of measurement data is naturally a crucial and important factor for a company to deliver the right quality to its customers. Without confidence in the measurement data, there is a potential risk that the customers end up with defective products if the measurement results are misinterpreted. This thesis project has been conducted at Volvo GTO in Skövde at the crankshaft manufacturing department. Volvo GTO wants to understand how well their manufacturing process of crankshaft performs by assigning a capability value. One of the requirements for obtaining a reliable capability value is that the measurement system is reliable. Volvo suspects that they do not have a reliable measuring system for measuring the roundness of bearing surfaces on a crankshaft. To clearly identify the problems of the measurement system, several possible causes of errors were identified and then analyzed deeper. These possible causes have attempted to be disproved and the errors which couldn’t be disproven may be a possible cause of error. The result of this thesis project shows that the company doesn’t meet the requirements to perform reliable measurements with such small tolerances. The main cause of the uncertainty in the measurement process is the external factors, such as the measuring environment. This report also includes recommendations on how the company can eliminate the measurement uncertainties to get a more reliable measurement process. / För att ett tillverkande företag ska kunna uppnå och bibehålla sin konkurrenskraft är kvalitetssäkring en viktig del av verksamheten. För att kunna uppmäta hur företagets processer presterar är det nödvändigt att företaget har tillförlitlig mätdata. Tillförlitlighet till mätdata är av naturliga skäl en avgörande och viktig faktor för att ett företag ska leverera rätt kvalitet till sina kunder. Utan tillit till mätdatan finns det en potentiell risk att defekta produkter hamnar hos kunden genom att tolka mätresultatet felaktigt. Detta examensarbete har utförts på Volvo Group Trucks Operations (GTO) i Skövde på vevaxels-avdelningen. Volvo GTO vill förstå hur väl deras tillverkningsprocess av vevaxlar presterar genom ett duglighetstal. Ett av kraven för att få ett pålitligt duglighetstal är att mätsystemet är tillförlitligt. Volvo anser idag att de inte har ett tillförlitligt mätsystem vid rundhetsmätning av vevaxlar. För att tydligare kartlägga de problem som idag finns med mätsystemet så identifierades ett antal felmöjligheter som analyserades djupare. Dessa felmöjligheter har försökts att motbevisas och de som inte har kunnat motbevisas kan vara en möjlig felorsak. Resultatet uppvisar att det finns brister i de grundförutsättningar som krävs för att en tillförlitlig mätning skall kunna utföras. I arbetets gång är det tydligt att det främst är de yttre faktorerna som skapar en osäkerhet i mätprocessen. Rapporten avslutas med en rekommendation kring hur företaget kan eliminera mätosäkerheten för att få en tillförlitligare mätprocess.
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Probabilistic procedures for lifetime management of reinforced concrete highway bridgesSterritt, Garry January 2000 (has links)
The UK’s bridge stock is deteriorating due to a number of mechanisms that affect concrete durability. These include carbonation, thaumasite sulphate reaction, alkali-silica reaction, chloride ingress, freeze-thaw action and fatigue. There are limited resources available to maintain the bridge stock in a safe and operable condition. It is therefore essential that available funds are used to optimum effect for inspections, maintenance, assessment, repair or replacement. If a short term view is taken to bridge management then it is highly likely that a future backlog of essential work will build up which will result in severe financial and operational difficulties. In this context, methodologies that can predict the time-dependent deterioration of RC bridges would be highly beneficial to bridge owners and maintaining agents when developing bridge management strategies. A methodology has been developed in this thesis to estimate the time-dependent deterioration and structural reliability of RC components. Only chloride induced deterioration was modelled because it was found to be the dominant mechanism in the UK. Probabilistic techniques and spatial analysis are used to model the uncertainty inherent to chloride induced deterioration. Code based limit state equations are used with the deterioration models to create time-dependent failure margins. Standard reliability methods (FORM/SORM) are then applied to estimate failure probability time profiles over the life of the bridge. Furthermore, classical and Bayesian statistical techniques are used to update deterioration/reliability predictions. The deterioration models produce plots of area initiated or delaminated as a function of time. These may be used to plan inspection times and types. The ensuing limit state reliability analysis produce probability of failure profiles which may be used as a comparative tool for assessing similar bridge/component types, and thus a bridge management strategy can be developed on the basis of perceived criticality. The updating techniques are used to illustrate how model predictions can be improved when site data becomes available. It is shown that the development of models using typically available site data can be beneficial to bridge owners, but the quantity of such data needs to be enhanced. This is particularly evident for the wide diversity of bridge structures in the UK.
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Supervision adaptative et pronostic de défaillance pour la maintenance prévisionnelle de systèmes évolutifs complexes / Adaptive supervision and prognosis of failure for predictive maintenance of complex evolutive systemsTraoré, Moussa Amadou 01 December 2010 (has links)
Une maintenance prévisionnelle efficace repose d’une part sur une modélisation précise de connaissances expertes préexistantes (AMDEC, Arbre de défaillance, etc.) et d’autre part sur des outils de supervision et de pronostic sensibles aux évolutions du procédé. La performance de ces outils repose sur l’analyse et l’estimation en temps réel de l’état du procédé, mais également sur la prévision de ses états futurs. Sur cette base, des indicateurs tels que les valeurs probabilistes issues du pronostic de défaillances peuvent être exploités pour la planification efficiente d’actions de maintenance. En partant des connaissances expertes préétablies, nous proposons une approche de supervision adaptative basée sur une technique de reconnaissance des formes, AUDyC (AUto-adaptive and Dynamical Clustering), qui est particulièrement adapté aux systèmes dynamiques évolutifs et complexes. Cette approche permet de suivre en temps réel l’état de fonctionnement du procédé, avec un minimum de connaissances a priori sur ses caractéristiques physiques, de détecter et de diagnostiquer tout changement de son comportement, même si le système évolue vers un état jusqu’alors inconnu et d’actualiser la base de connaissance par intégration de nouveautés. Une approche de pronostic de défaillance couplée au processus de supervision adaptative est alors proposée afin de fournir en temps réel, l’état futur d’un procédé tout en estimant la probabilité qu’une défaillance survienne à un instant futur ainsi que la fiabilité de ce pronostic. Cette architecture de supervision adaptative et de pronostic proposée est utilisée pour la maintenance prévisionnelle des composants d’un système réel de thermorégulation. / An effective predictive maintenance relies on the one hand, on an accurate modeling of available expert knowledge (Failure Mode, Effects and Criticality Analysis, Fault Tree, etc) and on the other hand, on monitoring tools that are sensitive to changes in the process under consideration. The performance of the monitoring tools consists not only in their ability to estimate and analyze the process state in real-time, but also in their capability to predict the future states. On this basis, indicators derived from the probabilistic prediction of failure occurrences can be exploited for the efficient planning of maintenance actions. Based on the predefined expert knowledge, we propose an approach of supervision based on a pattern recognition technique, the AUDyC algorithm (Auto-adaptive and Dynamical Clustering), which is particularly suitable for dynamic and complex systems monitoring. The proposed supervision approach allows us to (i) monitor the operational status of the system in real-time, with a minimum prior physical knowledge, (ii) detect and diagnose any change in the system behavior, even if the system evolves to a previously unknown state, (iii) update the basis of knowledge about the system by integrating new features into it. In order to provide in real-time an estimate of the future state of the system, a prognosis technique is coupled with the above mentioned supervision unit. This makes it possible to compute, with a certain reliability, the probability that a failure occurs at a given future time. Finally, the whole architecture for both supervision and prognosis is applied for the predictive maintenance of a real thermoregulation system.
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Concrete repair procedures suitable for typical South African conditionsJooste, A. J. C. 06 February 2012 (has links)
M.Ing. / It is generally accepted that successful concrete repair is dependent on seven steps. All seven steps of the concrete repair process were investigated in depth. From the seven steps, three of the steps (removal, application and curing) were selected for experimental investigation. Firstly, the removal of damaged concrete was simulated under laboratory conditions. Concrete blocks were prepared through different removal techniques. Repair material was placed on the blocks, and the adhesion between the concrete repair material and the concrete substrate was determined. Secondly, different repair mortar application methods were used, and the effect of application methods on adhesion strengths was determined. Thirdly, the effect of curing on adhesion was determined by curing samples under different conditions. Some in situ test repairs were done at RAU to get an indication of the appropriate repair systems to be used on the RAU buildings. A questionnaire was given out to the industry and analyzed to get an indication of the common practice used for concrete repair in South Africa.
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Methodology for aesthetic repair and rehabilitation of architectural concrete.Zhang, Yu 27 May 2008 (has links)
Structural concrete can be treated using a variety of special methods to produce aesthetically pleasing effects. This type of concrete is called architectural concrete. It is possible to produce structures with colourful, smooth or textured surface finishes that will satisfy any of the demands of modern architecture. It is clear that matching the colour and texture of repair work in architectural concrete is problematic. Concrete surfaces with different types of finishes require different rehabilitation processes, just as different ages of concrete require different repair methods. The concrete life cycle is set up for aesthetic repair in this research. Before a repair project is undertaken it is important to ascertain the type of failure. The causes of the failure should be identified and removed if possible. The factors influencing the appearance of the concrete surface should be discussed, in order that the right skills and technical methods are employed during the rehabilitation process. The repair method should be divided into two categories, one is for the young concrete, and another is for the old concrete. A good starting point for the patching mortar of both young and old architectural concrete are suggested as a result of the experiments. Two new factors have been established as a result of this research, namely the colour coefficient and the colour influence coefficient, both of which will be beneficial to future research projects. KEYWORDS: architectural concrete, colourimetric method, discolouration, young and old concrete, colour coefficient, colour influence coefficient. / Mr. Deon Kruger
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A model for integrating information security into the software development life cycleFutcher, Lynn Ann January 2007 (has links)
It is within highly integrated technology environments that information security is becoming a focal point for designing, developing and deploying software applications. Ensuring a high level of trust in the security and quality of these applications is crucial to their ultimate success. Therefore, information security has become a core requirement for software applications, driven by the need to protect critical assets and the need to build and preserve widespread trust in computing. However, a common weakness that is inherent in the traditional software development methodologies is the lack of attention given to the security aspects of software development. Most of these methodologies do not explicitly include a standardised method for incorporating information security into their life cycles. Meaningful security can be achieved when information security issues are considered as part of a routine development process, and security safeguards are integrated into the software application throughout its life cycle. This, in turn, will lead to users being more confident to use software applications, and to entrust today's computer systems with their personal information. To build better or more secure software, an improved software development process is required. Security of a software application must be based on the risk associated with the application. In order to understand this risk, the relevant information assets need to be identified together with their threats and vulnerabilities. Therefore, security considerations provide input into every phase of the Software Development Life Cycle (SDLC), from requirements gathering to design, implementation, testing and deployment. This research project presents a Secure Software Development Model (SecSDM) for incorporating information security into all phases of the SDLC, from requirements gathering to systems maintenance. The SecSDM is based on many of the recommendations provided by relevant international standards and best practices, for example, the ISO 7498-2 (1989) standard which addresses the underlying security services and mechanisms that form an integral part of the model.
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Continuous improvements of complex technical systems : aspects of stakeholder requirements and system functionsSöderholm, Peter January 2003 (has links)
In today's society we are all strongly dependent on correct functions of technical systems. These systems tend to increase in both complexity and criticality, at the same time as they often have a rather long life. During this long life the stakeholders' requirements on the functions of the systems change. In order to maintain a high level of stakeholder satisfaction organisations responsible for the system have to respond to the changes through system development and continuous improvements. When the technical system is both complex and critical it is even more important that the work with continuous improvements is done in a systemic and systematic way. This is because a modification may result in unwanted side effects and a small change in one part of the system may have a major negative impact on many other parts of the system, and also have far reaching decisive consequences. The purpose of this thesis is to explore and describe how an organisation can work with continuous improvements of complex technical system functions in the context of changing stakeholder requirements, in order to increase stakeholder satisfaction with a reduced amount of resources. To fulfil the stated purpose a case study supported by a literature study has been made. The case study focused on a modern combat aircraft, which is considered as a highly complex and safety critical system with stringent requirements on low life cycle cost. The result of the study may be described in two parts. The first part is a theoretical management framework that combines aspects of Quality Management, Requirements Management, and Health Management. The framework describes on a conceptual level how the work with continuous improvements may be enhanced through synergism achieved by the combination. The second part, which is based on both theoretical and empirical findings, is a model intended to support the work with continuous improvements. The model includes a number of combined and adapted methodologies and tools that enable traceability between stakeholder requirements and the critical system functions that should be covered by tools that support Condition Monitoring, Diagnostics, and Prognostics.
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Environmental management systems : policy implementation and environmental effectsZobel, Thomas January 2005 (has links)
Corporate environmental management is becoming less driven by regulatory compliance and more driven by corporate strategy. In order to gain competitive advantage, systematically assure regulatory compliance and develop more efficient operations an increasing number of organisation adopt the environmental management system (EMS) tool. Ever since the introduction of the EMS standard ISO 14001 in 1996, the effects of EMSs has been evaluated. Using meta-evaluation, the existing evidence on environmental effects of EMS is in this thesis evaluated. The reviewed studies are not consistent regarding benefits of EMS and it is therefore not possible to generally suggest a causal linkage between EMS implementation and improved environmental performance. Another meta-study in this thesis focused on the influence of different organisation characteristics on environmental effects of EMS. The results indicate that benefits of EMS seem to be inert of the drivers for adoption and the cultural setting. Large organisations as well as smaller ones benefit from EMS, but for different reasons. EMS appears to be a functional tool in the industrial sector but also in service organisations with complex environmental impact. EMS has the disadvantage that it is developed with larger organisations in mind. A common approach used by small and medium-sized organisations to facilitate the implementation of EMSs is joint EMS and group certification. Through a case study, it was found that the approach, despite a few short cuts, is effective for small and micro-sized companies in achieving ISO 14001 certification as fast and cost effective as possible. The identification and assessment of environmental aspects and the implementation of environmental policy through objectives, targets and programmes are in this thesis characterised by the use of two multiple-case studies. It is concluded that the implementation of environmental policy is strictly controlled by specifications in EMS standards. Some organisations are forced to design their environmental policy implementation in a way that is not suited for their type of organisation. Many organisations find it hard to measure their environmental goals and to set long-term or medium- long-term time periods for their goals. In addition, the organisations do not involve their employees to a very great extent in this policy implementation. Six problematic elements when identifying and assessing environmental aspects have been identified: definition of environmental aspects, update of aspects, aggregation of aspects, exclusion of business considerations in the assessment, employee and stakeholder participation, competence levels of people involved in the process. In addition, inadequacies exist regarding the reproducibility of the methods used for identification and assessment of environmental aspects. In order to improve the reproducibility, an approach to a new method is suggested which is based on life cycle analysis (LCA) methodology. / Organisationers miljöarbete drivs mindre och mindre av lagkrav och mer och mer av deras övergripande strategi. För att kunna vinna marknadsfördelar, systematiskt uppfylla lagkrav och utveckla mer effektiva processer, väljer ett ökande antal organisationer att införa miljöledningssystem (MLS). Ända sedan introduktionen av miljöledningsstandarden ISO 14001 har studier utförts för att utvärdera effekterna av MLS. Med hjälp av en meta-studie har existerande data gällande miljöeffekter av MLS utvärderats i denna avhandling. En granskning av tidigare studier visar att det inte är möjligt att fastställa ett causalt samband mellan införandet av MLS och förbättrad miljöprestanda. En andra meta-studie i denna avhandling har fokuserat på påverkan av olika organisationsfaktorer på miljöeffekterna av MLS. Resultaten visar att nyttan av MLS verkar vara oberoende av drivkrafterna för införande av MLS och den kulturella miljön. Både större och mindre organisationer verkar ha nytta av MLS, men av olika anledningar. MLS verkar vara ett fungerande verktyg i den industriella sektorn men även i serviceorganisationer med komplex miljöpåverkan. MLS är främst utvecklat för större organisationer. Ett vanligt angreppssätt för att underlätta införandet av MLS i små och medelstora organisationer är gruppcertifiering. En fallstudie visar att gruppcertifiering, trots en del genvägar, är ett effektivt sätt för små- och mikroföretag att införa MLS. Identifiering och värdering av miljöaspekter samt nedbrytning av miljöpolicy genom övergripande mål, detaljerade mål och förbättringsprogram har karakteriserats genom två multipla fallstudier. Studierna visar att nedbrytningen av miljöpolicy är strikt styrd av kraven i MLS-standarder. En del organisationer tvingas att utforma nedbrytningen av miljöpolicyn på ett sätt som inte är lämpat för dem. Många organisationer har svårt att mäta sina miljömål och att fastställa medellånga och långa tidsperioder för målen. Organisationerna verkar inte involvera sin anställda i särskilt stor omfattning vid nedbrytning av miljöpolicyn. Sex problematiska delmoments när miljöaspekter identifieras och värderas har identifierats; definition av miljöaspekt, uppdatering av miljöaspekter, gruppering av miljöaspekter, uteslutande av affärskriterier vid värdering av miljöaspekter, involvering av anställda och intressenter och kompetensnivåerna hos dem som utför arbetet. Dessutom finns brister i reproducerbarheten i rutinerna för identifiering och värdering av miljöaspekterna. Som ett försökt att förbättra reproducerbarheten har riktlinjer för en ny metod tagits fram. Metoden är baserad på livscykelanalys (LCA). / Godkänd; 2005; 20061001 (ysko)
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Quality improvements in forest products industry : classification of biological materials with inherent variationsGrönlund, Ulla January 1995 (has links)
Classifying logs and boards has an essential economic impact on the forest products industry. In contrast to other process industries the sawmills do not try to homogenize the raw material, but instead try to utilize the inherent properties of every single log and board in the best way. The aim of this thesis is to improve the quality control and decrease the costs for poor quality by introducing new methods to measure and describe the raw material. The work is focused on the grading procedures, and thereby 1) analyzing the relevance of the current classification systems and investigating the characteristics that are the most important ones in today´s grading procedures; 2) evaluating models developed to detect interior defects in logs automatically, giving suggestions for improvements; 3) suggesting ideas and methods for a classification system for tomorrow. The investigation comprises partly about 1100 Scots pine (Pinus silvetris) logs harvested on 16 randomly selected stands in Sweden and graded both by graders and by an automatic equipment; partly around 600 pine logs from permanent sample plots in Sweden and scanned by a CT-scanner (Computed tomography). The predictability between the grade of a log and its boards is very low, around 20%. Repeated investigations show that two graders assess the same grade on about 50% of the logs and boards, i.e., they judge the properties equally. The results also emphasize that the current manual classification systems are not in concordance with the customer´s demand and the natural variations in the material cannot be handled in an efficient way by current grading rules and transformed by human beings. The CT-scanner is used to measure the interior properties (defects) of a log. The validation of the methods and models shows that when the accuracy is improved for small knots, the models identify a knot with an accuray of +/- 5 mm. An embryo to a property index, PI, that gives an individual description of the inherent properties of logs and boards, is given. Based on customer-orientation and various strategies for describing log properties, a clustering procedure can be evaluated in order to form and describe appropriate classes (clusters, grades). Then, by an allocation rule with the function for assessing a grade, every single log or board can be automatically classified into one group. / Godkänd; 1995; 20070428 (ysko)
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