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  • 651.
    Andersson, Susanne
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Salihu, Ermira
    Blekinge Institute of Technology, School of Health Science.
    Palliativ omvårdnad: Det viktigaste i vården ur patienternas perspektiv2008Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Bakgrund: Oavsett om döendet äger rum i hemmet, på sjukhus eller hospice så har sjuksköterskan ett stort ansvar. Således krävs det att hon eller han har ingående kunskap om vad det kan innebära att vara svårt sjuk och vårdberoende för att kunna leverera en optimal vård. Den som bäst kan hjälpa oss som sjuksköterskor att förstå upplevelser av att vara döende; är patienten. Syfte: Belysa vad patienter i palliativ vård upplever som viktiga aspekter för sin omvårdnad. Metod: Litteraturstudie av åtta stycken kvalitativa vetenskapliga artiklar. Artikelsökningen gjordes via databaserna Elin@Blekinge och Academic Search Elite. Inklusionskriterier för sökningen var engelska och svenska studier på vuxna människor, ur ett patientperspektiv, publicerade mellan 1998 och 2008. Resultatet i artiklarna analyserades med innehållsanalys. Resultat: Ur analysens granskning växte följande åtta kategorier fram; Skydd av värdighet, Kommunikation, Goda relationer, Emotionellt stöd, Praktisk hjälp, Sjuksköterskans personlighet och professionalism, Leva till slutet samt Förberedelser och tankar inför döden. Dessa kategorierna talar för att patienter bör respekteras som individer med diverse behov som bör tillgodoses. Dessa utgör en helhet hos människan där varje del hör ihop och kan inte särskiljas eller utelämnas. Slutsats: Flertal aspekter visade sig vara av vikt för en positiv patientupplevelse av sin omvårdnad. Denna litteraturstudie belyser komplexiteten i palliativ omvårdnad och där helheten kan förklaras utifrån omvårdnadsteoretikern Katie Erikssons helhetssyn på människan i ett omvårdnadskontext. Speciellt viktigt ter det sig att sjuksköterskor förstår upplevelsen av att vara svårt sjuk, är lyhörda och individualiserar vården för att patienterna skall kunna uppleva optimal omvårdnad under sin sista tid.

  • 652.
    Andersson, Therese
    Blekinge Institute of Technology, Department of Business Administration and Social Science.
    Team: förväntningar och uppfattningar ur olika perspektiv2003Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Det finns idag få och i framtiden kanske ännu färre uppgifter som är av sådan karaktär att endast en person bäst löser dem. Det krävs som regel något slags samarbete, ofta i form av arbete i grupp eller arbetslag. I denna rapport har jag undersökt hur teamarbete uppfattas på arbetsplatsen, samt vilka förväntningar medarbetarna har över teamet och om dessa har uppfyllts. För att ta reda på min frågeställning har använt mig av en kvalitativ metod eftersom jag vill undersöka individers personliga förväntningar och uppfattningar om begreppet team. En fallstudie på tre olika företag har genomförts i form av intervjuer med produktionschef och teammedarbetare på respektive företag. Intervjuerna är semistrukturerade med öppna frågor. Genom min undersökning kom jag fram till att begreppet team uppfattas som något positivt av alla de personer jag intervjuade. Anledningen till varför är till exempel för att man hjälper varandra mycket, det är större frihet och många uppfattar det som roligt att ha företagets förtroende. Företagen uppfattar det också som något positivt då de får ut mycket av teamen i sig, att de når framgång rent kostnadsmässigt samt att de har nått upp till de mål som finns. Förväntningarna över teamen är många. Företagen hade mest förväntningar vad gäller att spara pengar, både administrativt och i produktionen. Ett företag utmärkte sig dock och menade att medarbetarna är viktigaste. Deras förväntningar var att personalen skulle lyfta sig och känna ansvar och förtroende för företaget. Samtliga av dessa förväntningar har uppfyllts. Teammedarbetarna hade andra förväntningar än företagen. De trodde det skulle bli lättare och bättre att arbeta, att de skulle veta lite vad alla gör, att hjälpas åt när och där det behövs och att det skulle bli bättre sammanhållning i grupperna. Samtliga av dessa har uppfyllts. Vissa hade dock inga förväntningar alls, eller i alla fall inga positiva. I dessa fall har inte förväntningarna uppfylls, då det blivit bättre än de förväntat sig.

  • 653.
    Andersson, Therese
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Neander, Sara
    Blekinge Institute of Technology, School of Health Science.
    Vilket stöd kan sjuksköterskan bistå överviktiga personer med för att motivera till förändrad livsstil och viktnedgång?2005Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Övervikt är idag vanligt förekommande bland personer på många håll i västvärlden. Detta förknippas med en förändrad livsstil. Många som har försökt gå ner i vikt på egen hand har ofta misslyckats på grund av otillräcklig motivation eller att de inte har haft det rätta stödet. Ett professionellt bemötande är därför väsentligt. Syftet med studien var att undersöka vilket stöd sjuksköterskan i mötet med överviktiga personer kan bistå med för att motivera till förändrad livsstil och viktnedgång. Metoden som använts var litteraturstudie. Resultatet visade att det är väsentligt att sjuksköterskan gör mötet till en positiv upplevelse för den överviktiga personen. Genom att visa empati och förståelse för personens känslor kan sjuksköterskan bygga en relation baserad på trygghet och tillit. Sjuksköterskan måste själv vara motiverad inför uppgiften för att kunna uppmuntra och stödja den överviktiga personen i viktnedgången. Det framkom även att sjuksköterskan inte enbart bör fokusera på själva viktnedgången utan lägga tyngdpunkten på hälsovinsterna som kommer av en beteendeförändring. I diskussionen framkom det att sjuksköterskans attityd och förmåga till empati var av stor betydelse för personens tillit. Genom en tydlig målsättning innehållande information, utbildning och involvering av familj och vänner kan sjuksköterskan bistå med stöd och motivera till förändrad livsstil och viktnedgång.

  • 654.
    Andersson, Therése
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Olsson, Ulrika
    Blekinge Institute of Technology, School of Health Science.
    Smärtan är min: Att leva med fibromyalgi2009Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Bakgrund: Patienter med fibromyalgi upplever att de sällan blir tagna på allvar då de på utsidan ser ut att må bra, men i själva verket har ont. Då smärtan inte syns ökar svårigheten att förklara smärtans påverkan för andra. Det är således en utmaning för patienter med fibromyalgi att få andra att förstå deras situation. Syfte: Att belysa kvinnors utsagor av att leva med fibromyalgi. Metod: Den metod som valdes var en analys av två självbiografiska böcker med en kvalitativ metod. Innehållsanalysen av böckerna utfördes enligt en samlad metodbeskrivning av Graneheim & Lundman (2004). Resultat: Sex kategorier framkom, dessa var: Möten, Fibromyalgi syns inte alltid, När det gör ont, Oberäknelighet, Accepterande samt Tankar om stöd. Slutsats: Sammanfattningsvis ses ett samband mellan de ej synbara symtomen och omgivningens brist på förståelse inför sjukdomens omfattning och påverkan. De som tar del av denna studie får möjligheten till att erhålla kunskap, förståelse samt få inblick i hur det är att leva med fibromyalgi.

  • 655.
    Andersson, Thomas
    et al.
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Arnevill, Anita
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    How can business partners establish a relationship of trust in order to share Web Services?2003Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    Introduction Web Services is a relatively new concept to distributed data systems. It provides a new way for companies to easily integrate with other companies. With UDDI, companies are able to host their services in a wider market and also connect to other companies. However, with business expansion also follows trust issues. In order to share Web Services in a business partner relationship it is necessary to have a relation of trust. Purpose The purpose of this thesis is to investigate about this issue, i.e. how Web Services with the use of UDDI can be made as a “network of trust” and additionally obtain an idea about how the use of these two will look like in the future. The question of trust between partners sharing Web Services is still open. There has therefore been an interest to look at this problem. The aim for this thesis is to find possible solutions that can be used to address the problem. Method To investigate this we chose to do a literature study and continue with a survey consisted by interviews and questionnaires. Interviews were used to find which solutions that are available in reality and the questionnaires provide information about to what extent Web services and the found solutions are used. The questionnaire was done on random Swedish companies and was sent by e-mails. The interviews were done on two global Swedish companies, Volvo and Ericsson. This way information was found and could be compared in how the issue is dealt with in the literature and what is actually done in reality. Conclusion The outcome of the entire investigation is that Web Services today, even though it exists in most companies, is still in testing phase. As for this, the use of UDDI has had little attention and so has the issues regarding trust. The solution we found to the most applicable to create a network of trust is the Liberty Alliance Project. Web Services, UDDI, trust

  • 656.
    Andersson, Tobias
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Software Engineering.
    Brenden, Christoffer
    Blekinge Institute of Technology, Faculty of Computing, Department of Software Engineering.
    Parallelism in Go and Java: A Comparison of Performance Using Matrix Multiplication2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis makes a comparison between the performance of Go and Java using parallelizedimplementations of the Classic Matrix Multiplication Algorithm (CMMA). The comparisonattempts to only use features for parallelization, goroutines for Go and threads for Java,while keeping other parts of the code as generic and comparable as possible to accuratelymeasure the performance during parallelization.In this report we ask the question of how programming languages compare in terms of multi-threaded performance? In high-performance systems such as those designed for mathemati-cal calculations or servers meant to handle requests from millions of users, multithreadingand by extension performance are vital. We would like to find out if and how much of a dif-ference the choice of programming language could benefit these systems in terms of parallel-ism and multithreading.Another motivation is to analyze techniques and programming languages that have emergedthat hide the complexity of handling multithreading and concurrency from the user, lettingthe user specify keywords or commands from which the language takes over and creates andmanages the thread scheduling on its own. The Go language is one such example. Is this newtechnology an improvement over developers coding threads themselves or is the technologynot quite there yet?To these ends experiments were done with multithreaded matrix multiplication and was im-plemented using goroutines for Go and threads for Java and was performed with sets of4096x4096 matrices. Background programs were limited and each set of calculations wasthen run multiple times to get average values for each calculation which were then finallycompared to one another.Results from the study showed that Go had ~32-35% better performance than Java between 1and 4 threads, with the difference diminishing to ~2-5% at 8 to 16 threads. The differencehowever was believed to be mostly unrelated to parallelization as both languages maintainednear identical performance scaling as the number of threads increased until the scaling flat-lined for both languages at 8 threads and up. Java did continue to gain a slight increase goingfrom 4 to 8 threads, but this was believed to be due to inefficient resource utilization onJava’s part or due to Java having better utilization of hyper-threading than Go.In conclusion, Go was found to be considerably faster than Java when going from the mainthread and up to 4 threads. At 8 threads and onward Java and Go performed roughly equal.For performance difference between the number of threads in the languages themselves nonoticeable performance increase or decrease was found when creating 1 thread versus run-ning the matrix multiplication directly on the main thread for either of the two languages.Coding multithreading in Go was found to be easier than in Java while providing greater toequal performance. Go just requires the ‘go’ keyword while Java requires thread creation andmanagement. This would put Go in favor for those trying to avoid the complexity of multi-threading while also seeking its benefits.

  • 657.
    Andersson, Veronica
    et al.
    Blekinge Institute of Technology, School of Management.
    Larsson, Ulrika
    Blekinge Institute of Technology, School of Management.
    Saranovic, Amra
    Blekinge Institute of Technology, School of Management.
    Delat ledarskap – En utvärdering av de verkliga effekterna2006Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [sv]

    Syfte: Vårt syfte med uppsatsen är att ur ett ledningsperspektiv se vilka verkliga effekter delat ledarskap leder till. Vi vill utvärdera om de av ledningen förväntade effekterna leder till de verkliga effekterna vi kunde se. Metod: Vi har använt oss av kvalitativ metod för att få en djup inblick i de verkliga effekterna i det delade ledarskapet. Vi har först tagit reda på vilka effekter ledarna ville uppnå, för att sedan göra en utvärdering varpå vi visar de verkliga effekter som uppstått. För att utföra detta har vi använt oss av ett antal fallstudier. Slutsats: Vi kan inte entydigt säga att de av ledningen planerade effekterna har uppnåtts i de organisationer vi har undersökt. Vi kan se att dessa delvis har infriats men på ett komplext vis och på bekostnad av andra effekter. Vi menar att problematiken ligger i att ledningen inte helt och hållet erhållit de avsiktligt planerade effekterna i någon av de organisationerna vi undersökt. Vi har även ställt oss frågan om vi tydligt kan separera effekterna helt och hållet från varandra eller om de är integrerade i varandra så att vi inte kan utesluta vare sig den ena eller andra. Men vi kan konstatera att dessa effekter som inte alltid är kostnadsfria troligtvis inte hade utvunnits utan delat ledarskap. Vi menar att ett välkoordinerat delat ledarskap kan uppnå önskade effekter. Förutsättningen för att de önskade effekterna skall uppnås är att ledningen är uppmärksam på de effekter de önskar och lyfter fram dem till ett synligt och medvetet utvecklingsläge.

  • 658.
    Andersson, Veronica
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Mårtensson, Kajsa
    Blekinge Institute of Technology, School of Health Science.
    Copingstrategier i forskning om främjandet av psykisk hälsa hos arbetslösa: En integrativ litteraturstudie2013Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Hälsopåverkan på grund av arbetslöshet är ett utbrett problem som påverkas av både samhälleliga och politiska faktorer. Brist på arbete medför många konsekvenser så som förlorad inkomst, ekonomisk sårbarhet och försämrad livskvalitet. Det finns ett klart samband mellan arbetslöshet och ohälsa med bemärkelse på psykisk ohälsa eftersom arbetslösa personer tenderar att ha sämre hälsa än arbetande personer. Coping handlar om hur individer reagerar på svåra eller stressande livssituationer. Hur en individ använder sig av olika copingstrategier påverkar hur denne hanterar den svåra livssituationen som arbetslöshet utgör. Syftet med studien var därmed att undersöka hur copingstrategier inkluderas i forskning om preventivt arbete för att främja psykisk hälsa vid arbetslöshet? Detta undersöks genom en integrativ litteraturstudie av fem vetenskapliga artiklar som fokuserar på sambandet mellan psykisk hälsa, arbetslöshet och coping. Den kvalitativa innehållsanalysen har resulterat i två teman; Copingstrategier i befintliga interventioner för arbetslösa & Copingstrategier som potentiell främjande faktor i interventioner/preventivt arbete. Dessa teman har sedan delats upp i fem underteman. Resultatet visade att copingstrategier inkluderas i forskning genom analyserande av preventiva interventioner samt i beskrivandet av copingstrategier kopplat till arbetslöshet. Copingstrategier inkluderas i denna forskning som en främjande faktor för psykisk hälsa samt återanställning. Vi efterlyser mer forskning på detta område för att kunna säkerställa hur interventioner som inkluderar kunskaper om copingstrategier och hur individer hanterar stressade och utsatta situationer påverkar den arbetslöses psykiska hälsa.

  • 659.
    Andersson, Veronica
    et al.
    Blekinge Institute of Technology, Department of Business Administration and Social Science.
    Wernersson, Cecilia
    Blekinge Institute of Technology, Department of Business Administration and Social Science.
    Individuell lönesättning som styrmedel: en jämförelse mellan praktiken och några teoretiskt fastställda faktorer.2002Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Syfte: Syftet är att se om de verksamheter som säger att de tillämpar individuell lönesättning, verkligen gör det? Metod: Vi har valt att göra en uppsats med både kvantitativ och kvalitativ inriktning. Underlaget för undersökningen har varit intervjuer med 19 respondenter i fyra olika verksamheter. Slutsatser: I tre av de fyra fall vi undersökt kan vi konstatera att den individuella lönesättningen inte fungerar.

  • 660.
    Andersson, Viktor
    et al.
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Lindgren, Daniel
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Ranking factors to increase your positionon the search engine result page: Theoretical and practical examples2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Search engine optimization (SEO) is the way to improve the visibility of a website on thesearch engine result page (SERP). If the website is not on the first three result, then it will bemissing most of the traffic that could be generated. This report will go into detail on how towork with SEO and how to get a website to rank high. Both On-page, how to work with codeand content, and Off-page, how to get more links, methods will be discussed, with a higherfocus on On-page.This paper strives to find what methods and techniques to use with the results gathered fromscientific databases, interviews and three websites with different levels of SEOimplementation. How to structure the code, where and how to use keywords, domain name,links and much more will be discussed in this paper.

  • 661.
    Andersson, Viktoria
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Rydell, Marcus
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Hur är det att leva med en närstående som har schizofreni?2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: I dag har ca 30 000 – 40 000 svenskar av schizofreni som är den mest svårförstådda psykossjukdomen. Personer som lider av schizofreni är i stort behov av stöd ifrån deras närstående. Det är även vanligt att vården lägger över ett stort ansvar på närstående när den sjuke är i hemmet. Att vara närstående till en person som lider av schizofreni kan vara mycket krävande och ha en stor påverkan på deras livssituation. Det är en del av sjuksköterskans roll ta reda på närståendes upplevelse och erfarenhet och att involvera närstående i vårdandet för att på så sätt kunna förbättra omvårdnaden av personen med schizofreni.

    Syfte: Syftet med denna studie var att beskriva upplevelsen av att leva med en närstående som har diagnosen Schizofreni.

    Metod: En systematisk litteraturstudie med kvalitativ ansats som baserades på nio vetenskapliga artiklar som analyserades enligt Graneheim och Lundmans innehållsanalys.

    Resultat: Resultatet i studien visade att de närståendes upplevelse var mycket komplex och varierande. De närståendes upplevelse beskrev oftast genom emotionella upplevelser som påverkades utav olika faktorer. De olika faktorerna som påverkade de närstående var sjukdomen, stigma, kunskap och stöd.

    Slutsats: I studien framkom det att närståendes upplevelse var väldigt komplexa och påverkades av många olika faktorer. De närstående till en person som lider av schizofreni upplevde en stark påverkan både på deras livssituation, framtidssyn och emotionella känslor, och genom ökad kunskap och stöd kunde deras upplevelse förändras.

  • 662.
    Andoh, Mavis
    Blekinge Institute of Technology, School of Management.
    THE RELATIONSHIP BETWEEN LEADERSHIP STYLE AND SAFETY CLIMATE: A CASE STUDY OF GOLDFIELDS GHANA LIMITED, TARKWA-CIL PLANT2013Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    The management of efficient and effective work place safety in order to reduce occupational accidents is one of the paramount interests of stakeholders of the mining industry. Leadership behavior is an important factor in achieving safety performance in an organization. An organization’s leadership style can be the cause of accidents and incidents at the workplace. The way in which safety and health is led and integrated into an organization can impact significantly on wellbeing at work, including addressing problems of worker absence through ill-health. The overall goal of the research is to identify different dimensions of leadership style that have influence on safety climate in general and be able to determine the relationship between the two. In this study, the research questions are addressed in order to study the relationship between leadership style and safety climate. Two questionnaires were used to gather data from employees at the Goldfields Ghana Limited, CIL Plant, comprising supervisors (leaders), technicians (subordinates). The study used the Multifactor Leadership Questionnaire (MLQ) formulated from Bass and Avolio’s (1997) Full Range Leadership Development Theory to determine leadership style within the organization and the Nordic Occupational Safety Climate Questionnaire (NOSACQ-50) to determine the safety climate. The relationship indicated that Transformational Leadership styles correlated with a better safety climate than Transactional Leadership style. The study identified the leadership style that contribute to good safety environment thereby paving way to how safety performance can be improved at Goldfields Ghana Limited which may result in increase in revenue and maximization of shareholders value.

  • 663.
    Andreasson, Eskil
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Mechanics and Failure in Thin Material Layers: Towards Realistic Package Opening Simulations2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The final goal of this PhD-work is an efficient and user-friendly finite element modelling strategy targeting an industrial available package opening application.  In order to reach this goal, different experimental mechanical and fracture mechanical tests were continuously refined to characterize the studied materials. Furthermore, the governing deformation mechanisms and mechanical properties involved in the opening sequence were quantified with full field experimental techniques to extract the intrinsic material response. An identification process to calibrate the material model parameters with inverse modelling analysis is proposed. Constitutive models, based on the experimental results for the two continuum materials, aluminium and polymer materials, and how to address the progressive damage modelling have been concerned in this work. The results and methods considered are general and can be applied in other industries where polymer and metal material are present.                                                                   

    This work has shown that it is possible to select constitutive material models in conjunction with continuum material damage models, adequately predicting the mechanical behaviour in thin laminated packaging materials. Finally, with a slight modification of already available techniques and functionalities in a commercial general-purpose finite element software, it was possible to build a simulation model replicating the physical behaviour of an opening device. A comparison of the results between the experimental opening and the virtual opening model showed a good correlation.

    The advantage with the developed modelling approach is that it is possible to modify the material composition of the laminate. Individual material layers can be altered, and the mechanical properties, thickness or geometrical shape can be changed. Furthermore, the model is flexible and a new opening design with a different geometry and load case can easily be implemented and changed in the simulation model. Therefore, this type of simulation model is prepared to simulate sustainable materials in packages and will be a useful tool for decision support early in the concept selection in technology and development projects.

  • 664.
    Andreasson, Eskil
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Realistic Package Opening Simulations: An Experimental Mechanics and Physics Based Approach2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    A finite element modeling strategy targeting package opening simulations is the final goal with this work. The developed simulation model will be used to proactively predict the opening compatibility early in the development process of a new opening device and/or a new packaging material. To be able to create such a model, the focus is to develop a combined and integrated physical/virtual test procedure for mechanical characterization and calibration of thin packaging materials. Furthermore, the governing mechanical properties of the materials involved in the opening performance needs to be identified and quantified with experiments. Different experimental techniques complemented with video recording equipment were refined and utilized during the course of work. An automatic or semi-automatic material model parameter identification process involving video capturing of the deformation process and inverse modeling is proposed for the different packaging material layers. Both an accurate continuum model and a damage material model, used in the simulation model, were translated and extracted from the experimental test results. The results presented show that it is possible to select constitutive material models in conjunction with continuum material damage models, adequately predicting the mechanical behavior of intended failure in thin laminated packaging materials. A thorough material mechanics understanding of individual material layers evolution of microstructure and the micro mechanisms involved in the deformation process is essential for appropriate selection of numerical material models. Finally, with a slight modification of already available techniques and functionalities in the commercial finite element software AbaqusTM it was possible to build the suitable simulation model. To build a realistic simulation model an accurate description of the geometrical features is important. Therefore, advancements within the experimental visualization techniques utilizing a combination of video recording, photoelasticity and Scanning Electron Microscopy (SEM) of the micro structure have enabled extraction of geometries and additional information from ordinary standard experimental tests. Finally, a comparison of the experimental opening and the virtual opening, showed a good correlation with the developed finite element modeling technique. The advantage with the developed modeling approach is that it is possible to modify the material composition of the laminate. Individual material layers can be altered and the mechanical properties, thickness or geometrical shape can be changed. Furthermore, the model is flexible and a new opening device i.e. geometry and load case can easily be adopted in the simulation model. Therefore, this type of simulation model is a useful tool and can be used for decision support early in the concept selection of development projects.

  • 665.
    Andreasson, Eskil
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Håkansson, Paul
    Sandgren, Martin
    Jönsson, Joel
    Deformation and Damage Mechanisms in Thin Ductile Polymer Films2013Conference paper (Refereed)
    Abstract [en]

    The mechanical material behavior of highly extensible or ductile polymer films used in the packaging industry has been studied in this work. The polymer material, consisting of different variants of polyethylene grades, is used as several components in the packaging material structure at Tetra Pak®. Experimental tensile tests were used to quantify the mechanical behavior and to be able to calibrate numerical constitutive material models. The studied polymer materials were able to withstand large deformations before breaking, involving both necking in the width and thickness direction of the specimen. During deformation re-orientation of polymer chains and substantial strain-hardening were also occurring. The latter effect was accounted for in the presented material modeling approach. The numerical simulations were solved in the general finite element software Abaqus version 6.13. In this work a continuum damage modeling (CDM) approach was used. CDM which are attractive in macro scale applications, thus solving our engineering problems, was chosen in this study due to the computational efficiency. A damage model consisting of two functionalities; initiation of damage and evolution of damage was suitable for modeling the ductile fracture behavior. During the numerical analysis it has been assumed that the polymer materials are isotropic, homogenous through the thickness, independent of strain rate and independent of temperature to ease the material parameters identification.

  • 666. Andreasson, Eskil
    et al.
    Jemal, Abdulfeta
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Katangoori, Rahul Reddy
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Is it possible to open beverage packages virtually? Physical tests in combination with virtual tests in Abaqus.2012Conference paper (Refereed)
    Abstract [en]

    The opening mechanism in a beverage package, where a mixed mode failure occurs, is a rather complex phenomenon. A better knowledge in respect of fracture mechanics is needed for the proactive prediction of the overall opening performance. Reliable material data used for virtual simulation of the opening mechanism is extracted by characterization and calibration of the packaging materials. Knowledge of how to choose appropriate constitutive models for the continuum material and how the damage initiates and propagates to various loading conditions is of great interest. The virtual tests, replicating the physical tests, are performed with the aid of the finite element method. Non-linear material response, anisotropic material behaviour, large deformation and fracture mechanics are identified effects that are all included in the virtual model. The results presented in this paper show possible selections of material models in conjunction with material damage models, adequately describing thin polymer films behaviour. Comparison between the physical test and the virtual test, exerted to fracture Mode I – Centre Cracked Tension, showed a good correlation for the chosen modeling technique.

  • 667.
    Andreasson, Eskil
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Jönsson, Joel
    Tetra Pak, SWE.
    Advancements in package opening simulations2014In: Procedia Materials Science / [ed] Zhang, Z; Skallerud, B; Thaulow, C; Ostby, E; He, J, Elsevier, 2014, Vol. 3, p. 1441-1446Conference paper (Refereed)
    Abstract [en]

    The fracture mechanical phenomenon occurring during the opening of a beverage package is rather complex to simulate. Reliable and calibrated numerical material models describing thin layers of packaging materials are needed. Selection of appropriate constitutive models for the continuum material models and how to address the progressive damage modeling in various loading scenarios is also of great importance. The inverse modeling technique combined with video recording of the involved deformation mechanisms is utilized for identification of the material parameters. Large deformation, anisotropic non-linear material behavior, adhesion and fracture mechanics are all identified effects that are needed to be included in the virtual opening model. The results presented in this paper shows that it is possible to select material models in conjunction with continuum material damage models, adequately predicting the mechanical behavior of failure in thin laminated packaging materials. Already available techniques and functionalities in the commercial finite element software Abaqus are used. Furthermore, accurate descriptions of the included geometrical features are important. Advancements have therefore also been made within the experimental techniques utilizing a combination of microCT-scan, SEM and photoelasticity enabling extraction of geometries and additional information from ordinary experimental tests and broken specimens. Finally, comparison of the experimental opening and the virtual opening, showed a good correlation with the developed finite element modeling technique.

  • 668.
    Andreasson, Eskil
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Kao-Walter, Sharon
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Ståhle, Per
    Micro-mechanisms of a laminated packaging material during fracture2014In: Engineering Fracture Mechanics, ISSN 0013-7944, E-ISSN 1873-7315, Vol. 127Article in journal (Refereed)
    Abstract [en]

    The micro-mechanisms of fracture in a laminate composed of an aluminium foil and a polymer film are considered in this study. The laminates as well as the individual layers, with and without premade centre-cracks, were tensile tested. Visual inspection of the broken cross-sections shows that failure occurs through localised plasticity. This leads to a decreasing and eventually vanishing cross-section ahead of the crack tip for both the laminate and their single constituent layers. Experimental results are examined and analysed using a slip-line theory to derive the work of failure. An accurate prediction was made for the aluminium foil and for the laminate but not for the freestanding polymer film. The reason seems to be that the polymer material switches to non-localised plastic deformation with significant strain-hardening.

  • 669.
    Andreasson, Eskil
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Lindström, Tommy
    Lunds Universitet, SWE.
    Käck, Britta
    Altair Engineering AB, SWE.
    Malmberg, Christoffer
    Saab AB, SWE.
    Asp, Ann Magret
    Tetra Pak AB, SWE.
    Simulation of thin aluminium-foil in the packaging industry2017In: AIP Conference Proceedings / [ed] Brabazon D.,Ul Ahad I.,Naher S., American Institute of Physics Inc. , 2017, Vol. 1896, article id 160014Conference paper (Refereed)
    Abstract [en]

    This work present an approach of how to account for the anisotropic mechanical material behaviour in the simulation models of the thin aluminium foil layer (≈10 μm) used in the Packaging Industry. Furthermore, the experimental results from uniaxial tensile tests are parameterised into an analytical expression and the slope of the hardening subsequently extended way beyond the experimental data points. This in order to accommodate the locally high stresses present in the experiments at the neck formation. An analytical expression, denominated Ramberg-Osgood, is used to describe the non-linear mechanical behaviour. Moreover it is possible with a direct method to translate the experimental uniaxial tensile test results into useful numerical material model parameters in Abaqus™. In addition to this the extended material behaviour including the plastic flow i.e. hardening, valid after onset of localisation, the described procedure can also capture the microscopic events, i.e. geometrical thinning, ongoing in the deformation of the aluminium foil. This method has earlier successfully been applied by Petri Mäkelä for paperboard material [1]. The engineering sound and parameterised description of the mechanical material behaviour facilitates an efficient categorisation of different aluminium foil alloys and aid the identification of the correct anisotropic (RD/TD/45°) mechanical material behaviour derived from the physical testing. © 2017 Author(s).

  • 670.
    Andreasson, Eskil
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Mehmood, Nasir
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Kao-Walter, Sharon
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Trouser tear tests of two thin polymer films2013Conference paper (Refereed)
    Abstract [en]

    Trouser tear testing has been concerned in this research work. A polypropylene film and a low density polyethylene film used in the packaging industry are considered. The experimental trouser tear tests showed different results for both materials when they were subjected to load in different material directions. Therefore the hypothesis was verified, that the in-plane material orientation/alignment induced during manufacturing, hence creating anisotropic in-plane mechanical properties, also affects the tearing behavior. A brittle-like failure was shown in the polypropylene film while the low density polyethylene presented a highly ductile behavior. The two polymer films can be classified as one low-extensible and one high-extensible material according to the test method utilized. Material parameters in the principal material directions i.e. manufacturing direction and cross direction were extracted from the experimental tests for further numerical studies. Scanning electron microscope was used for micromechanical and fractographical analysis of the crack tip and crack surfaces created during the tests. The methods discussed will help classify different groups of materials and can be used as a predictive tool for the crack initiation and crack propagation path in packaging material, especially thin polymer films.

  • 671.
    Andreasson, Eskil
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Mehmood, Nasir
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Mao, Tan
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    An Experimental, Numerical and SEM Study of Fracture in a Thin Polymer Film2014In: MATERIALS STRUCTURE & MICROMECHANICS OF FRACTURE VII, Trans Tech Publications Inc., 2014, Vol. 592-593, p. 225-+-Conference paper (Refereed)
    Abstract [en]

    Observations and analysis of samples from scanning electron microscopic (SEM) micrographs has been concerned in this work. The samples originate from fractured mechanical mode I tensile testing of a thin polymer film made of polypropylene used in the packaging industry. Three different shapes of the crack; elliptical, circular and flat, were used to investigate the decrease in load carrying capacity. The fracture surfaces looked similar in all studied cases. Brittle-like material fracture process was observed both by SEM micrographs and the experimental mechanical results. A finite element model was created in Abaqus as a complementary tool to increase the understanding of the mechanical behaviour of the material. The numerical material models were calibrated and the results from the simulations were comparable to the experimental results.

  • 672.
    Andreasson, Eskil
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Mehmood, Nasir
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Mao, Tan
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Kao-Walter, Sharon
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Experimental and Numerical fracture of cracks emanating from different types of flaws in thin polymer films2013Conference paper (Refereed)
    Abstract [en]

    Fracture mechanical Mode I tensile testing has been performed on an oriented polyproplyne film used in packaging industry. Physical Tensile testing for the continuum material has been performed to observe the material strength and to extract continuum material properties for numerical analysis. Fracture mechanical testing of different shaped notches is performed to observe the failure initiation in the material. A brittle-like failure was shown in the polypropylene film while the low density polyethylene presented a highly ductile behavior. A finite element method (FEM) strategy has been successfully developed to perform numerical analysis of polymer films. The developed FEM model gives an accurate and approximate method to compare and analyze the experimental and numerical results. The obtained results have shown a very fine similarity under theoretical, experimental and numerical analysis. Depending on crack geometry different shape crack effects showed the transferability of localized stresses at different points around the crack. Fracture surface and fracture process is analyzed using scanning electron microscope (SEM). Brittle failure with small deformation and presence of small voids and their coalescence has also been shown in SEM micrographs for LDPE material. The methods discussed will help classify different groups of materials and can be used as a predictive tool for the crack initiation and crack propagation path in packaging material, especially thin polymer films.

  • 673.
    Andreasson, Eskil
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Persson, Leo
    Jacobsson, Henrik
    Nordgren, Johan
    Integrating Moldflow and Abaqus in the Package Simulation Workflow2013Conference paper (Refereed)
    Abstract [en]

    Tetra Pak has used numerical simulation tools for plastic injection molding (Moldflow) and structural analysis (Abaqus/Implicit and Abaqus/Explicit) for many years. Today these two simulation tools are used independently of each other without any coupling. How these two disciplines can be combined to better predict the mechanical response of a polymer component is presented in this work. The manufacturing process, in this case injection molding, creates the mechanical properties of the produced polymer part. Process settings, material selection and molding tool geometry affect the polymer flow, material orientation and rate of crystallinity. A method to build a layered finite element model in Abaqus using results from Moldflow simulations regarding crystallinity growth and molecular orientation is proposed. Relatively simple material models were utilized and assigned for each individual material layer through the thickness in the polymer part. These constitutive models were derived phenomenologically from experimental test results and could adequately capture both the microscopic and the macroscopic behavior in a more realistic way. The numerical results showed a good agreement with the experimental results, both regarding visual appearance and force/displacement response.

  • 674.
    Andreasson, Mathias
    et al.
    Blekinge Institute of Technology, School of Technoculture, Humanities and Planning.
    Ekesrydh, Wynona
    Blekinge Institute of Technology, School of Technoculture, Humanities and Planning.
    Nielsen, Pia
    Blekinge Institute of Technology, School of Technoculture, Humanities and Planning.
    Schertell, Mattias
    Blekinge Institute of Technology, School of Technoculture, Humanities and Planning.
    Ansökan om körkortstillstånd via Internet2003Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Länsstyrelsen i Stockholms län hade en projektidé som gick ut på att det skulle skapas en Internetbaserad ansökan för körkortstillstånd med behörighet B, inklusive hälsodeklaration. Även en optiker skulle kunna fylla i ett synundersökningsformulär via webben. Dessa skulle sedan knytas ihop för behandling av den Länsstyrelse där den sökande bor. Alla personer som skall använda tjänsten måste inneha ett personligt medborgarcertifikat som används för elektronisk signering av ansökan. Optikern behöver ett företagscertifikat för att identifiera sig. Vi utvecklade två interaktiva användargränssnitt samt ett gränssnitt där administratören kunde hantera all data som inkommit. All data transporterades med hjälp av Web Services (SOAP/XML). För att strukturera upp datan gjordes ett XML-schema som används för validering vid transporten. Allt dvs ansökan, hälsodeklaration och synundersökning landar sedan i en databas där all data knyts ihop som tillhör en sökande. Vi förberedde även användargränssnittet, databasen och XML-strukturen för fortsatt utveckling som t ex ansökan om andra körkortsbehörigheter och läkarintyg. Under utvecklingen använde vi erfarenheter tagna från tidigare lästa kurser och omsatte teorier till praktik, både inom projektledning, -drift, -planering och teknologiska kunskaper. Vi tog tillvara på tidigare kurser samt utforskade nya områden inom vår valda inriktning som är webbprogrammering där Web Services ingår. Via litteratur och Internet sökte vi information som värderades. Hela arbetsprocessen genomfördes efter en iterativ produktutvecklingsmetod. Vi utvärderade och omvärderade resultat och delresultat i en ständigt pågående spiralprocess.

  • 675.
    Andrej, Sekáč
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Performance evaluation based on data from code reviews2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Context. Modern code review tools such as Gerrit have made available great amounts of code review data from different open source projects as well as other commercial projects. Code reviews are used to keep the quality of produced source code under control but the stored data could also be used for evaluation of the software development process.

    Objectives. This thesis uses machine learning methods for an approximation of review expert’s performance evaluation function. Due to limitations in the size of labelled data sample, this work uses semisupervised machine learning methods and measure their influence on the performance. In this research we propose features and also analyse their relevance to development performance evaluation.

    Methods. This thesis uses Radial Basis Function networks as the regression algorithm for the performance evaluation approximation and Metric Based Regularisation as the semi-supervised learning method. For the analysis of feature set and goodness of fit we use statistical tools with manual analysis.

    Results. The semi-supervised learning method achieved a similar accuracy to supervised versions of algorithm. The feature analysis showed that there is a significant negative correlation between the performance evaluation and three other features. A manual verification of learned models on unlabelled data achieved 73.68% accuracy. Conclusions. We have not managed to prove that the used semisupervised learning method would perform better than supervised learning methods. The analysis of the feature set suggests that the number of reviewers, the ratio of comments to the change size and the amount of code lines modified in later parts of development are relevant to performance evaluation task with high probability. The achieved accuracy of models close to 75% leads us to believe that, considering the limited size of labelled data set, our work provides a solid base for further improvements in the performance evaluation approximation.

  • 676.
    Andresen, Mario
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Technology and Aesthetics.
    Johnsson, Daniel
    Blekinge Institute of Technology, Faculty of Computing, Department of Technology and Aesthetics.
    Analysmetod för designade ljudbilder: Skapandet av nya förhållningssätt för ljuddesign2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Syftet med detta kandidatarbete var att framställa en analysmetod för dekonstruktion av ljuddesign i film. Målet med analysmetoden var att skapa ett förhållningssätt för ljuddesigners som gör det enklare att lära sig från ljudläggningar och genom övning eventuellt kunna bidra till ett mer avancerat sätt att tänka på vad ljud kan göra i en filmproduktion.

    Metoden är tänkt som ett stöd för blivande ljuddesigners som lärt sig tekniska kunskaper men kämpar med den kreativa biten där problemen inte har lika konkreta lösningar. Metoden är också tänkt som ett supplement till mer erfarna ljuddesigners för övning på sina kunskaper ellerförbättring av deras egen process.

    Vi tycker metoden nådde upp till de målen, men den visade sig också vara mer flexibel än så. Genom applicering av metoden inför arbete med vår gestaltning där vi ljudlade ett filmklipp blev designprocessen mycket enklare att komma igenom. Vi tror därför att en metod som vår kan vara en viktig del i att få in ljud tidigare i en filmproduktion.

  • 677.
    André, Daniel
    Blekinge Institute of Technology, School of Technoculture, Humanities and Planning.
    Polycentrism in national spatial plans in Europe: towards a common spatial vision?2009Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    In this thesis I analyze how national spatial plans that have been adopted in European countries during the last decade have interpreted the polycentric development concept. A survey revealed that fifteen European countries have developed a national spatial plan and the formal influence of the European Spatial Development Perspective (ESDP) is clearly demonstrated in these plans. The development visions presented in the spatial planning documents are, at a formal level, relatively homogenous regardless of national differences regarding the size of the population and the geographical area. In the thesis I also pose the question whether the national spatial plans will contribute towards a polycentric development on a European level. The findings presented in the thesis suggest that even though the national spatial plans have been inspired by the ESDP and its aim of developing a polycentric development the interpretation of polycentrism on the national level seem to be contradictory to the policy aim at the European level. Also, the Swedish planning experience of the 1960/70s highlights the difficult task of prioritising the development in some cities at the expense of others. Thus, it is concluded that even if the spatial plans are better coordinated so that they contribute towards a common spatial vision it is still highly doubtful that they will be able to deliver on their objective to create a more balanced urban system.

  • 678.
    Andréason, Nanna
    et al.
    Blekinge Institute of Technology, School of Technoculture, Humanities and Planning.
    Hellman, Camilla
    Blekinge Institute of Technology, School of Technoculture, Humanities and Planning.
    Wengle, Sara
    Blekinge Institute of Technology, School of Technoculture, Humanities and Planning.
    Dokumentär om döden2004Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Vi har som kandidatarbete gjort ett dokumentärfilmsprojekt. Filmen handlar om barns och pensionärers tankar och funderingar om döden. Vi ville göra en annorlunda dokumentär som väcker känslor utan att provocera. Döden är något som man inte ofta talar om och därför kände vi att vi ville ta upp detta ämne i en seriös men ganska lättsam film. Vi bestämde att lägga tyngdpunkten på research för att få en så bra grund som möjligt. Eftersom ämnet kan väcka många känslor ville vi vara förberedda på alla slags reaktioner. Under projektets gång har vi planerat vecka för vecka vad vi ska göra samt följt en övergripande tidsplan. Vi har också varje vecka skrivit en rapport om vad vi har gjort, vilka problem som vi har haft och vad som har fungerat bra. Vi tog kontakt med ett dagcenter och ett dagis och hittade bra människor att intervjua. De var alla mycket hjälpsamma och våra inspelningar gick bra. Vi var mycket nöjda med våra bilder och även ljudet. I klippningen har vi sett dokumentären växa fram och vi har haft lätt att se vilka klipp som passar in och vilka som inte gör det. Projektet har flutit på relativt smidigt och när problem har uppstått har vi lyckats lösa dem efter hand. Vi har lärt oss mycket och blivit säkrare på oss själva. Det har varit nyttigt för oss att arbeta med utomstående och med olika åldersgrupper. Att vi har skapat externa kontakter har också varit en bra erfarenhet. Vi har lärt oss att samarbeta och att lyssna på varandra. Det är viktigt att alla får komma till tals i en så här liten grupp. Vi tycker att det har varit spännande att göra ett sådant här stort projekt. Det har varit skönt att ha mycket tid till förfogande och att vi har fått lägga upp och genomföra projektet helt själva. Vi har utvecklats under projektets gång och vi känner oss nöjda med både projektet och slutresultatet.

  • 679.
    Andréasson, David
    Blekinge Institute of Technology.
    En annan upplaga av oss: Cyborgens implementation i samhället2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Cyborg, a shared setting of the words cybernetics and organism, a figure whose meaning should be seen as more than a fictional creation. The cyborg is today, according to scientists and philosophers a social reality and its impact on the individual is much greater than we can imagine. This bachelor thesis investigates what defines a cyborg, with support from research and philosophy thoughts and approach are summed up to get a more definitive picture of the concept. The work also studies how the social context may be distorted when the technology finds its way into the physical body. The results and insights this work resulted in is summarized and stands as the basis for a design whose goal has been to categorize open data from individuals with built-in RFID chip, a discussion of the concept and its meaning is summarized in the results section to get a broad picture of the whole cyborg. Methods such as workshops and literature studies have helped to get a broader picture of the human way of living together with technology.

  • 680.
    Andrén, Christina
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Hammami, Karim
    Blekinge Institute of Technology, School of Health Science.
    Experiences of newly qualified nurses of University of Limpopo, Turfloop Campus executing mandatory community service in Limpopo Province, South Africa.2011Student thesis
    Abstract [en]

    Background: Anxiety because of lack in organization and management skills, fear of legal disputes and the possibility of losing their professional registration is real concerns of nurses in the immediate period of post-qualification. Many of the countries in Sub-Saharan Africa, as South Africa, are facing severe shortages of skilled health staff. One of the most important factors is the exodus of health care staff, which is largely a symptom of other health system deficits. Aim: To determine the experiences of newly qualified nurses of University of Limpopo, Turfloop Campus executing mandatory community services in Limpopo Province, South Africa. Method: Seven participants were recruited for individual interviews in this study. The qualitative conducted individual interviews were analysed using a content analysis in four steps inspired by Burnard (1996). Result: The most revealing results were the many factors leading to a lot of distress to the nurse staff, which is a strong influence to the abandonment of the profession. These factors are all in turn consequences of the lack of financial resources put in to the health care system in South Africa. These include low salary, lack of material resources, shortage of the staff and lack of organisation of management. The balance between education, work situation and compensation seems to be flawed. Conclusion: The nursing education did not meet up to the requirements regarding the preparation for the nurses. Mandatory community service does not dissolve the main issues of abandonment. The salary seems to be the critical factor leading to abandonment of the nursing profession.

  • 681.
    Andrén, Emma
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Technology and Aesthetics.
    Davidsson, Sara
    Blekinge Institute of Technology, Faculty of Computing, Department of Technology and Aesthetics.
    Ego formatae: En studie i designprocessens agentiella perspektiv och påverkan på dess designer2019Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    I denna undersökning tar vi upp hur en designprocess kan ses ur ett agentiellt perspektiv. Detagentiella perspektivet är framtaget av Karen Barad som i sin forskning i kvantfysik börjadeundersöka hur olika fenomen kunde ta olika former, som till exempel hur ljus kunde ta bådepartikel- och vågform (2003). Genom att applicera detta perspektiv på hur man uppfattar

    verklighet och situationer utifrån olika håll ges möjlighet till en bredare bild av hur verklighets-skapande blir till. Vi ville därmed undersöka detta i relation till designprocess och hur

    verkligheten formas om man ser designprocessen ur dess eget perspektiv istället för designerns,samt hur designern blir formad av processen. Vi har valt att analysera faktorerna tid,informationshantering, process, designperspektiv, Psykofysiologi och medietekniskinstallationskonst. Vi har även valt att studera Chions (1994) begrepp audiovisuella kontraktet,som har varit en grund till vår valda design, genom agentiell realism.Vår design är byggd på intra-aktion, som förklarar mötet mellan olika faktorer som påverkar ensituation (agenser), och audiovisuella kontraktet, som förklarar samspelet mellan ljud, bild ochåskådare, där vi valt att utgå ifrån medieteknisk installationskonst. Med dessa somutgångspunkt skapades en design av en interaktiv Projection mapping, som kan förklaras somen projektion i flera lager, som samspelar med en ljudbild.

    Vi har under processens gång funnit fler exempel på hur vi som designers och individer harformats och förändrat olika ställningstaganden till både processen och vår verklighet, som viresonerat och diskuterat kring. Valet av vår undersökning är grundat på att ge ännu enkunskapsbas för vad som händer under en designprocess och för att medvetandegöra perspektivsom kan underlätta arbetsflödet. Vad händer egentligen med oss i en designprocess, och hurpåverkas designen?

  • 682.
    Andrén, Fredrik
    Blekinge Institute of Technology, Department of Human Work Science and Media Technology.
    Communication in SOS Alarm and the Possibility of Enhancement2004Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    When an accident is happening most of the time it is the person on the street that is reporting this to SOS Alarm, the instance that is controlling, for example, the ambulances. To ensure that as few mistakes as possible are made it us crucial that the communication between the caller and the ambulance via the SOS Alarm is as efficient as possible. Communication between the caller to SOS Alarm and the ambulance is done by passing through the operator at the SOS Alarm station and then on to the ambulance. Is this the way that it should be handled or are there optional ways that could be used? The technology has evolved since the system used today was installed and today cellular phones are very common and it is not unusual that it is possible to take pictures with these phones. Is this something that could be used to enhance the way information is sent between the caller and the ambulance? These are questions that this thesis tries to answer by using studies at SOS Alarm and Ambulance centrals as a foundation for the arguments.

  • 683. Andrén, Linus
    Active suppression of vibration and noise in industrial applications2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Today, active control technology is about to emerge from the research labs into products in various areas. It has become an attractive method where passive techniques have low impact at low frequencies and adding active control to that part is often an attractive solution. The active control technique has been enabled by the rapid development of digital signal processors over the last decades. The focal point in this thesis is active vibration and noise suppression. Two different industrial applications have been subjected to active control to reduce unwanted disturbances. In cutting operations, active vibration suppression has been applied to both external turning and boring operations with successful results. Turning operations, and in particular boring operations, are typical examples of chatter prone machining. In order to implement active vibration control in boring operations a thourough investigation of the boring process has been made in the first two parts in this thesis. The following two parts of the thesis treat active vibration suppression in external turning operations and in boring operations. The second industrial application treats the noise in a fork-lift truck. In the final part of the thesis, active noise suppression has been implemented in the cabin of a fork-lift truck.

  • 684. Andrén, Linus
    et al.
    Håkansson, Lars
    Active Vibration Control of Boring Bar Vibrations2004Report (Other academic)
    Abstract [en]

    The boring operation is a cumbersome manufacturing process plagued by noise and vibration-related problems. A deep internal boring operation in a workpiece is a classic example of chatter-prone machining. The manufacturing industry today is facing tougher tolerances of product surfaces and a desire to process hard-to-cut materials; vibrations must thus be kept to a minimum. An increase in productivity is also interesting from a manufacturing point of view. Penetrating deep and narrow cavities require that the dimensions of the boring bar are long and slender. As a result, the boring bar is inclined to vibrate due to the limited dynamic stiffness. Vibration affects the surface finish, leads to severe noise in the workshop and may also reduce tool life. This report presents an active control solution based on a standard boring bar with an embedded piezo ceramic actuator; this is placed in the area of the peak modal strain energy of the boring bar bending mode to be controlled. An accelerometer is also included in the design; this is mounted as close as possible to the cutting tool. Embedding the electronic parts not only protects them from the harsh environment in a lathe but also enable the design to be used on a general lathe as long as the mounting arrangements are relatively similar. Three different algorithms have been tested in the control system. Since the excitation source of the original vibrations, i.e. the chip formation process cannot be observed directly, the algorithms must be constructed on the basis of a feedback approach. Experimental results from boring operations show that the vibration level can be reduced by 40 dB at the resonance frequency of a fundamental boring bar bending mode; several of its harmonics can also be reduced significantly.

  • 685. Andrén, Linus
    et al.
    Håkansson, Lars
    Brandt, Anders
    Claesson, Ingvar
    Identification of Dynamic Properties of Boring Bar Vibrations in a Continuous Boring Operation2004In: Mechanical systems and signal processing, ISSN 0888-3270, E-ISSN 1096-1216, Vol. 18, no 4, p. 869-901Article in journal (Refereed)
    Abstract [en]

    Vibrations in internal turning operations are usually a cumbersome part of the manufacturing process. This article focuses on the boring bar vibrations. Boring bar vibrations in alloyed steel, stainless steel and cast iron have been measured in both the cutting speed direction and the cutting depth direction with the aid of accelerometers. The dynamic response of a boring bar seem to be a time varying process that exhibits non-linear behaviour. The process is influenced by non-stationary parameters that are not under the control of the operator or experimenter. The vibrations are clearly dominated by the first resonance frequency in one of the two directions of the boring bar. The problem with force modulation in rotary machinery, which appears as side band terms in the spectrum, is also addressed. Furthermore, the resonance frequencies of the boring bar are correlated to an Euler-Bernoulli beam model.

  • 686. Andrén, Linus
    et al.
    Håkansson, Lars
    Brandt, Anders
    Claesson, Ingvar
    Identification of Motion of Cutting Tool Vibration in a Continuous Boring Operation: Correlation to structural Properties2004In: Mechanical systems and signal processing, ISSN 0888-3270, E-ISSN 1096-1216, Vol. 18, no 4, p. 903-27Article in journal (Refereed)
    Abstract [en]

    The internal turning operation has a history of being a cumbersome metal working process as vibration in boring operations is usually inevitable. In this article, the deflection shapes and/or mode shapes as well as the resonance frequencies of a boring bar have been put under scrutiny. Three methods have been used in order to investigate dynamic properties of a clamped boring bar: a theoretical Euler-Bernoulli beam model, an experimental modal analysis and an operating deflection shape analysis. \\ The results indicate a correlation between the shapes of the deflection shapes and/or mode shapes produced by the three different analysis methods. On the other hand, the orientation of the forced deflection shapes and/or mode shapes and the resonance frequencies demonstrates differences between the three methods. During continuous cutting, it is demonstrated that the bending motion of the first two resonance frequencies is to a large extent in the cutting speed direction.

  • 687. Andrén, Linus
    et al.
    Håkansson, Lars
    Claesson, Ingvar
    Active Control of Boring Bar Vibrations Using the Leaky Feedback Filtered X-LMS2003Conference paper (Refereed)
    Abstract [en]

    The boring operation is a cumbersome manufacturing process marred by noise and vibration related problems. The manufacturing industry is having trouble with these kinds of metal cutting operations. There exist several approaches to reduce the vibrations in cutting operations in general. Passive tuned dampers in boring bars have been commercially available for some time. An active solution is likely to be more robust to changes in the spectral content, where the passive counterpart have a small operable area, the active solution is able to adapt to these kinds of changes. Active vibration control in boring operations has been proven to be feasible. The algorithm used in the successful experiments was the feedback filtered X-LMS algorithm. This algorithm does however not guarantee a stable behavior, but incorporating a leakage factor will make the algorithm more robust. Power spectral density of boring bar vibration of real cutting experiments show that the leaky filtered X-LMS algorithm is a possible candidate to be a suitable control algorithm. Nyquist diagrams of the controller during operation show that the stability is increased significantly.

  • 688. Andrén, Linus
    et al.
    Håkansson, Lars
    Claesson, Ingvar
    Active Control of Machine Tool Vibrations in External Turning Operations2003In: Proceedings of the Institution of mechanical engineers. Part B, journal of engineering manufacture, ISSN 0954-4054, E-ISSN 2041-2975, Vol. 217, no 6, p. 869-872Article in journal (Refereed)
    Abstract [en]

    Vibration and noise in metal cutting are ubiquitous problems in the workshop. The external turning operation is one kind of metal cutting that exhibits vibration related problems. Severe noise is also a problem growing in proportion due to regulations in preventing hearing loss. Active vibration control is a potential solution to such problems. With the piezo ceramic actuator technology of today, the size of the actuator can be kept small and still be able to produce a sufficient amount of force for the anti vibrations. Results from several continuous cutting experiments show a 40 dB reduction of the cutting tool vibration level. The design of the active technique enables this technology to be applicable to a general lathe provided the mounting arrangement is fairly similar.

  • 689. Andrén, Linus
    et al.
    Håkansson, Lars
    Claesson, Ingvar
    Actuator placements and Variations in the Control Path estimates in the Active Control of Boring Bar Vibrations2004Conference paper (Refereed)
    Abstract [en]

    A classical example of chatter prone machining is the boring operation. Turning under conditions with high vibrations in the cutting tool deteriorates the surface finish and may cause tool breakage. Severe noise is also a consequence of the high vibration levels in the boring bar. Active control is one possible solution to the noise and vibration problem in boring operations. In boring operations the boring bar usually have vibration components in both the cutting speed and the cutting depth direction. The introduction of the control force in different angles in between the cutting speed and the cutting depth directions have been investigated. Furthermore, control path estimates produced when the active boring bar was not in contact with the workpiece and during continuous cutting operation are compared. Experimental results indicate that the control force should be introduced in the cutting speed direction. Although the vibrations are controlled in just the cutting speed direction the vibrations in the cutting depth direction are also reduced significantly.

  • 690. Andrén, Linus
    et al.
    Håkansson, Lars
    Claesson, Ingvar
    Performance Evaluation of Active Vibration Control of Boring Operations Using Different Active Boring Bars2003Conference paper (Refereed)
    Abstract [en]

    Vibration and noise in boring operations are ubiquitous problems in the workshop. In boring operations, the boring bar is subjected to forces from both the cutting speed and the cutting depth direction. To solve the vibration problem using active techniques would normally require two actuators in order to enable the control of both directions. By mounting one actuator in between the cutting speed and the cutting depth direction it is possible to achieve an active control solution with one actuator. Using only one actuator not only simplifies the control algorithm and saves extra equipment but is also favourable in terms of modifications of the boring bar. The harsh environment in a lathe more or less requires that both sensors and actuators are embedded and sealed into the boring bar. Since the forces that are to be controlled are large, the space needed for the actuator is substantial. Thus using only one actuator will keep the modified boring bar stiffer than a two actuator design. Three boring bars with the actuator mounted at different angles between the cutting speed and the cutting depth directions have been tested. Results from cutting experiments show that the one actuator solution has good potentials to the vibration problem in boring operations.

  • 691. Andrén, Linus
    et al.
    Håkansson, Lars
    Claesson, Ingvar
    Lagö, Thomas L
    Piezo Ceramic Actuators versus High Magnetostrictive Actuators in the Active control of Tool Vibration1999Conference paper (Refereed)
    Abstract [en]

    In the turning operation chatter or vibration is a frequent problem, which affects the result of the machining, and, in particular, the surface finish. Tool life is also influenced by vibration. Severe acoustic noise in the working environment frequently occurs as a result of dynamic motion between the cutting tool and the workpiece. These problems can be reduced by active control of machine-tool vibration. In the active control system for the control of tool vibration a tool holder construction with integrated high magnetostrictive actuators was used. However, high magnetostrictive actuators generally have a non-linear behavior and it is a well known fact that non-linear properties in the forward path in an active control system is likely to degrade the robustness of the control system. A new generation embedded active tool holder shanks based on piezo ceramic actuators has been developed. Based on spectrum estimates, both coherence spectrum and frequency response function estimates has been calculated for both the old tool holder construction and the new generation active tool holder shank. From the results it follows that the phase delay is smaller and the linearity of the new generation active tool holder shank are superior compared to the old technology. The physical features and properties of the new generation active tool holders are superior to the old tool holder.

  • 692. Andrén, Linus
    et al.
    Johansson, Sven
    Winberg, Mathias
    Claesson, Ingvar
    Active Noise Control Experiments in a Fork-lift Truck Cabin2004Conference paper (Refereed)
    Abstract [en]

    High comfort for the driver in working vehicles is an important feature as well as a demand from the drivers. Low noise level is an essential factor for the manufacturer to maintain a high standard and comfort of vehicles. In many cases the noise inside the cabin can be related to the engine orders. Hydraulic pumps and fans are also related to the engine but not necessarily integers of the engine order. Passive absorbers are not suitable for the lowest frequencies and one approach is to use an active noise control system to solve the noise problem at low frequencies. In the present experiment loudspeakers were mounted inside the cabin of a fork lift-truck to produce the secondary noise field. To sense the residual noise, microphones were installed close to the driver's head. The aim is to create a zone of reduced noise around the head. Since a large portion of the noise inside the cabin can be related to the engine, an active control system based on a feedforward solution is possible. Experimental results from a feedforward solution of active noise control in a fork-lift truck cabin show that the noise level in the low frequency region can be reduced significantly.

  • 693.
    Andrén, Sebastian
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Industrial Economics.
    Sahyouni, Mohamad
    Blekinge Institute of Technology, Faculty of Engineering, Department of Industrial Economics.
    Exploring the Impact of the Project Management Office on Project Performance, A Quantitative Study2019Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Purpose - The purpose of this study is to explore the relationship between the establishment of a Project Management Office and project performance. Particularly, whether or not the establishment of a Project Management Office leads to enhanced project performance in project based organizations.

     

    Framework - The framework developed for the purpose of this study is made out of the different categories of Project Management Office services and functions on the one side and the different dimensions of project performance on the other. The model created tests the individual relationships between the constructs on each side.

     

    Methodology- The study employs a quantitative research design. Project Management Offices in organizations from across the globe and operating in a range of industries and industry segments are investigated. The data for the study is collected using an online questionnaire.

     

    Findings - The findings of this study lead to the belief that the establishment of a Project Management Office and the implementation of a certain set of its services and function will indeed lead to enhanced project performance

     

    Managerial Implications - Managers are made aware of the impact of the Project Management Office on project performance. Moreover, they are given guidelines as to what services and functions to adopt if there were only interested in seeing results on the project level.

    Limitations - The approach to exploring the subject in hand, the choice of participating organizations, the size of the sample tested, and the framework chosen for the evaluation of project performance are all seen as limitations for this study.

  • 694.
    Andrén, Åse Larsen
    et al.
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Mantzakanis, Tove
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Blom, Maria
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Säkerhets lösning för elektronisk faktura2002Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    We have chosen to look closer at the area of security for electronic invoices. The purpose of this inquest is to provide our case study with a security analysis of three suggestions and a recommendation of the best solution, according to our test. The three solutions are ISDN via a third party, X.25 via Internet bank and Mail server. The company in our case study is in this report referred to as X, has a strong market position and a large clientele and therefore we were interested in analysing and improving X?s electronic invoice system. X was in the position of testing an electronic invoicing system towards a selective group of business customers. The major problem with the system was the security issue regarding transferring the file.

  • 695.
    Andén, Calle
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Technology and Aesthetics.
    Moyle, Alexander
    Blekinge Institute of Technology, Faculty of Computing, Department of Technology and Aesthetics.
    Artem ex Machina: En undersökning av emergence som fenomen och som metod vid skapandet av posthumanistisk konst2017Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Detta kandidatarbete är en undersökning av begreppet emergence och hur det kan användas i skapandet av digital interaktiv konst. Vi undersöker sambandet mellan designern och datorn, och hur användaren kan interagera med båda dessa för att bidra till och utforma skapandet.

     

    För att demonstrera detta har vi skapat en simulation, som är tänkt att efterlikna tidigt mänskligt beteende på hög nivå: uppståndelsen av civilizationer, interaktion mellan folkgrupper, och utnyttjande av naturliga resurser. Vi diskuterar de etiska och politiska konsekvenserna som följer på skapandet av en sådan simulation, och vilken sorts interaktion vi främjar i vår design.

  • 696.
    Anehov, Ellen
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Thilly, Natcha
    Blekinge Institute of Technology, Faculty of Engineering, Department of Health.
    Hur bra kan en larvig behandling läka sår?: En systematisk litteraturöversikt2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Sår är ett underskattat hälsoproblem inom svenska sjukvården och kostar samhället mycket pengar. Sjuksköterskan har det yttersta ansvaret vid omvårdnaden för dessa patienter. Det ingår i kompetensbeskrivningen för sjuksköterskeprofessionen att evidensbaserad omvårdnad ska tillämpas. Larvterapi är en av de äldsta behandlingsmetoden för sårläkning, när antibiotikan slog igenom på 1940-talet ersattes larvterapi med antibiotikan. I samband med antibiotikaresistensen som uppkom på 1990-talet har alltfler forskare och läkare valt att återgå till larvterapi. 

    Syfte: Syftet med studien var att jämföra larvterapi med traditionella behandlingar avseende debridering av sår, antimikrobiella egenskaper, sårläkningstid, kostnadseffektivitet och smärta. 

    Metod: En systematisk litteraturöversikt baserad på nio artiklar med kvantitativ ansats och evidensgradering enligt GRADE. 

    Resultat: Resultatet presenterades i två översiktstabeller och delades in i fem variabler, dessa var debridering, antimikrobiella egenskaper, sårläkningstid, kostnadseffektivitet och smärta. Larvterapi visade en tydlig effektivitet vid debridering av sår jämfört med förband. dock var smärta vanligare i denna patientgruppen. Gällande antimikrobiella egenskaper, sårläkningstid och kostnadseffektivitet sågs ingen märkbar skillnad mellan larvterapi och traditionella behandlingar. 

    Slutsats: Larvterapi är en effektivare metod vid debridering av sår än traditionella förband och/eller kompression. Dock krävs det mer forskning gällande antimikrobiella egenskaper, sårläkningstid och kostnadseffektivitet. 

  • 697. Angelin, Lars
    On the Properties of a Congestion Control Mechanism for Signaling Networks Based on a State Machine1996Report (Other academic)
    Abstract [en]

    Congestion control in signaling systems is a necessity to fulfil the requirements of a tele-communication network that aims satisfy the customers’ requirements on service quality. Heavy network load is an important source of customer dissatisfaction as congested net-works result in deteriorated service quality. Sessions of a signaling service with high real time demands which are subject to unacceptable delays may be obsolete or prematurely terminated by the customer; in either way, they are a burden to the signaling network. It would ease the load of the network and improve the performance of all sessions in progress, if such delayed sessions could be aborted as quickly as possible. By measuring the network delay on individual signals of a service session, it is possible to perform signaling network congestion control that considers the state in the entire signaling network. Under the assumption that a session comprises a sequence of signals between one originating node and an arbitrary number of destination nodes, it is possible to predict the total duration of a session. The prediction is calculated from previously completed signals using a state machine, which is defined per signaling link. The annihilation of sessions, for which the prediction exceeds a predefined time limit, is an embryo of a simple signaling network congestion control mechanism (CCM). This simple CCM increases the number of successfully completed services with several hundred percent under favorable circum-stances. The state machine approach is proven to perform well in all types of environ-ments. The robustness and stability of the proposed CCM is demonstrated in a wide range of environments. The fairness in the admission of signaling services into the network at very high loads are also shown to be good.

  • 698. Angelin, Lars
    et al.
    Arvidsson, Åke
    A Congestion Control Algorithm for Signalling Networks Based on a State Machine Controlled by Network Delays1995Conference paper (Refereed)
    Abstract [en]

    Congestion control in Signaling System number 7 faces new challenges as mobile com-munication systems and Intelligent Networks grow rapidly. New services change traffic patterns, add to signalling network load, and raise demands on shorter service completion times. To handle new demands, the congestion control mechanisms must foresee an over-load situation, and respond to it so that the network can maintain high throughput. With the introduction of a state machine and a memory function for each signaling link it is possible to predict the completion time of a service session and to detect an emerging congestion. If the predicted completion time of a service session is too long, the session is annihilated. This is the foundation of a congestion control mechanism that reacts fast on information supplied by the network. The congestion control mechanism enables the network to main-tain a high throughput during overload.

  • 699. Angelin, Lars
    et al.
    Arvidsson, Åke
    A Congestion Control Mechanism for Signaling Networks based on Network Delays1995Conference paper (Refereed)
    Abstract [en]

    Congestion control in Signaling System #7 faces new challenges as mo-bile communication systems and Intelligent Networks grow rapidly. New ser-vices change traffic patterns, add to signalling network load, and raise demands on shorter service completion times. To handle new demands, the congestion control mechanisms must foresee an overload situation, and respond to it so that the network can maintain high probability for successful service comple-tion. With the introduction of a state machine and a memory function for each signaling link it is possible to predict the completion time of a service session and to detect an emerging congestion. If the predicted completion time of a service session is too long, the session is annihilated. This is the foundation of a congestion control mechanism that reacts fast on information supplied by the congested part of the network. The congestion control mechanism increases the ratio of successfully completed service sessions during congestion by several hundred percent.

  • 700. Angelin, Lars
    et al.
    Arvidsson, Åke
    On the Robustness of a Congestion Control Algorithm for Signaling Networks Based on a State Machine1996Conference paper (Refereed)
    Abstract [en]

    Sessions of a signaling service with high real time demands which are subject to unaccept-able delays may be obsolete or prematurely terminated by the customer; in either way, they are a burden to the signaling network. It would ease the load of the network and im-prove the performance of all sessions in progress, if such delayed sessions could be abort-ed as quickly as possible. By measuring the network delay on individual signals of a service session, it is possible to perform signaling network congestion control that consid-ers the state in the entire signaling network. Under the assumption that a session comprises a sequence of signals between one originating node and an arbitrary number of destination nodes, it is possible to predict the total duration of a session. The prediction is calculated from previously completed signals using a state machine, which is defined per signaling link. The annihilation of sessions, for which the prediction exceeds a predefined time limit, is an embryo of a simple signaling network congestion control mechanism (CCM). This simple CCM increases the number of successfully completed services with a few hundred percent under favorable circumstances. The state machine approach has been proven to function well in all types of environments. The robustness and stability of the proposed CCM is demonstrated and the fairness in the admission of signaling services into the net-work at very high loads are also shown.

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