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  • 1.
    AKTAR, SHAMIMA
    Blekinge Institute of Technology, Faculty of Engineering, Department of Spatial Planning.
    Urban Public Space: A Case from Developing Country2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Cities in developing world are inadequately equipped with public spaces. The increasing urbanizations trend is attracting more people to come to the cities without having proper sustainable plan for public spaces. However, this social public place holds the important function for urban well-being and collective recognition. This is the place where human can participate as fully fledged social subjects in complex civic life. Unfortunately, in most cases the provision of public space in these cities is always neglected or poorly integrated in planning legislations. So, in many cases community people make their own ways of social interaction that gives public space a new definition. Khulna, one of the divisional cities of Bangladesh, is going through the similar developing country situation. Lack of fund and space restricts development agencies to make new public spaces in this city. On the other hand management and coordination challenges between multilevel planning authorities also making existing public spaces malfunctioned. Sustainably planned, created and managed public spaces are hence urged for the cities of developing world to get livable and healthy urban environment.

  • 2.
    allouh, mahmoud
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Electrical Engineering.
    Gomez, Carlos
    Blekinge Institute of Technology, School of Engineering, Department of Electrical Engineering.
    Shockwarner for a Smartphone2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 3. Bengtsson, PerOlof
    Architecture-Level Modifiability Analysis2002Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Cost, quality and lead-time are three main concerns in software engineering projects. The quality of developed software has traditionally been evaluated on completed systems. Evaluating the product quality at completion introduces a great risk of wasting effort on software products with inadequate system qualities. It is the objective of this thesis to define and study methods for assessment, evaluation and prediction of software systems’ modifiability characteristics based on their architecture designs. Since software architecture design is made early in the development, architecture evaluation helps detect inadequate designs and thus reduces the risk of implementing systems of insufficient quality. We present a method for architecture-level analysis of modifiability (ALMA) that analyses the modifiability potential of a software system based on its software architecture design. The method is scenario-based and either compares architecture candidates, assesses the risk associated with modifications of the architecture, or predicts the effort needed to implement anticipated modifications. The modification prediction results in three values; a prediction of the modification effort and the predicted best- and worst-case effort for the same system and change scenario profile. In this way the prediction method provides a frame-of-reference that supports the architect in the decision whether the modifiability is acceptable or not. The method is based on the experiences and results from one controlled experiment and seven case-studies, where five case studies are part of this thesis. The experiment investigates different ways to organize the scenario elicitation and finds that a group of individually prepared persons produce better profiles than individuals or unprepared groups.

  • 4. Björkman, Christina
    Crossing Boundaries, Focusing Foundations, Trying Translations: Feminist Technoscience Strategies in Computer Science2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis I explore feminist technoscience strategies in computer science, starting in “the gender question in computer science”, and ending up in communication and translation between feminist technoscience research and computer science educational practice. Necessary parts in this work concern issues of boundary crossings between disciplines, and focusing on the foundations of computer science: what it means to “know computer science”. The point of departure is in computer science (CS), in particular CS education. There are at this starting point two intertwined issues: the gender question in computer science (often formulated as “what to do about the situation of women in computer science?”) and the foundation question: “what does it mean to know computer science?”. These are not primarily questions looking for answers; they are calls for action, for change and transformation. The main focus and goal of this thesis concerns how to broaden the meaning of “knowing computer science”; to accommodate epistemological pluralism and diversity within the practices and among the practitioners of CS. I have identified translation as fundamental, to make feminist research and epistemological perspectives communicable into the community of computer science practitioners. In this, questions of knowledge and how knowledge is perceived and talked about are central. Communication and translation also depend on the ability and willingness to cross boundaries, to engage in “world- travelling” (Lugones). Additional issues of importance are asking questions open enough to invite to dialogues, and upholding critical (self) reflection. An important goal for feminist research is transformation. Because of this, interventions have been part of my research, interventions in which I myself am implicated. The work has been based in feminist epistemological thinking, where the concepts of positioning and partial perspectives (Haraway) have been of particular importance. After an introduction, the thesis consists of three parts, each part relating to one of the three issues in the title, issues identified as important for feminist technoscience work in computer science. In part A, I investigate and discuss what it means to be simultaneously an engineer/computer scientist and a feminist technoscience researcher. What boundary crossings, challenges, conflicts, negotiations and issues of being inside and outside are involved? This part also focuses on what the implications of these boundary crossings and different “mind-sets” are for transformatory work in science and engineering education, as well as a discussion of what feminist technoscience research can be and how it can be used for interventions and transformations. Part B focuses on foundations of computer science. This part consists of studies of texts, which I critically read and query from a feminist technoscience perspective, in order to challenge existing approaches and concepts within computer science. The texts are about the gender question in computer science; foundational topics of “what is computer science”, as well as epistemological questions concerning approaches to knowledge in computer science: “what does it mean to know computer science”? Part C deals with a concrete intervention project aiming at establishing conversations with computer science faculty. In this project, the issues of communication and translation appear as central. The focus in this part is communication between computer science educational practice and feminist technoscience research, language as a carrier of epistemology, and a discussion of translation.

  • 5. Broberg, Magnus
    Performance Prediction and Improvement Techniques for Parallel Programs in Multiprocessors2002Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The performance of a computer system is important. One way of improving performance is to use multiprocessors with several processors that can work in parallel. Where multiprocessors are used, the programs must also be parallel in order to achieve high performance. However, it is not always easy to write parallel programs for multiprocessors; program developers need support in this area. Such support includes, for example, information regarding how well the parallel program scales-up when the number of processors increases and identification of performance bottlenecks; ideally, the result should be presented graphically. Bottlenecks arise both as a result of parallelization as well as traditional (sequential) code. Further, the developer may need to predict performance on other systems than the one used for development, since the development environment often is the (uni-processor) workstation on the developer's desk. One way of increasing the performance may be to bind threads on processors statically. Finding the optimal allocation is NP-hard and it is necessary to resort to heuristic algorithms. When heuristic algorithms are used we do not know how near/far we are from the optimal allocation. Finding a bound for the program's completion time shows what should be achievable using a heuristic algorithm. In this thesis, I present techniques how to simulate a multiprocessor execution of a parallel program based on a monitored execution on a uni-processor. The result of the (simulated) multiprocessor execution is graphically presented in order to give feedback to the developer. The techniques can be used for heuristic algorithms to find an allocation of threads to processors. Further, I show an algorithm that identifies the critical path of the parallel program on a multiprocessor, thereby identifying the segments that are worthwhile optimizing. I also show how to calculate a tight bound on the minimal completion time for the optimal allocation of threads to processors. Finally, I discuss the implications of the choice of simulation model. The techniques and algorithms described have been manifested in a prototype tool which I have used to perform empirical studies. The tool has been validated using a real multiprocessor.

  • 6. Carlsson, Bengt
    Conflicts in Information Ecosystems2001Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The main topic of this thesis concerns the study of how conflicting interests of software agents within an information ecosystem may cause cooperative behavior. Since such agents act on the behalf of their human owners, which often act in their own interest, this will sometimes result in malignant acts. Different types of models, often inspired by biological theories such as natural selection, will be used to describe various aspects of such information ecosystems. We begin by adopting a game theoretic approach where a generous and greedy model is introduced. Different agent strategies for iterated games are compared and their ability to cooperate in conflicting games are evaluated in simulation experiments. The conclusion is that games like the chicken game favor more complex and generous strategies whereas in games like the prisoner’s dilemma, the non-generous strategy tit-for-tat often is the most successful. We then use models based on a surplus value concept to explain antagonistic group formations. The focus is on systems that consist of exploiter agents and agents being exploited. A dynamic protection model of access control is proposed, where a chain of attacks and countermeasures concerning the access are measured. This process can be described as an arms race. It is argued that arms race is a major force in the interaction between antagonistic agents within information ecosystems. Examples of this are given in several contexts such as peer-to-peer tools concerning anonymity and non-censorship, using agents for sending or filtering out mass distributed advertisement e-mails, and finally for describing the fight against viruses or spywares.

  • 7. Dahl, Mattias
    Applied Array-Filter Design: Methods and Applications2000Doctoral thesis, comprehensive summary (Other academic)
  • 8. Elovaara, Pirjo
    Angels in Unstable Sociomaterial Relations: Stories of Information Technology2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    I have explored spaces, where negotiations of border transgressions take place and where issues of technology and politics mingle. We meet a diversity of actors in the world of information technology (IT): political texts, people and technology participating in numerous sociomaterial relations. Time is the end of the 1990s and the beginning of the new millennium, 2000. Years, when IT occupied the western world and created its own fuzzy discourse. Years, when IT stole the biggest newspaper headlines and years, when IT became a mundane everyday part of our work practices. Years, when we learned to live in heterogeneous worlds. Actor-Network Theory (ANT) and Actor-Network Theory and After (ANTa) provide analytical and methodological perspectives when working with the empirical material. I present a chronological exposé of some of the key concepts of ANT and ANTa. I also discuss how the classical ANT perspective has changed during the last few years from being a theory of networks to become a methodological and analytical approach to other kinds of spaces such as fluid and fire. The heart of the thesis consists of six empirical cases. My aim of writing stories of information technology has been to investigate the black box of information technology. Investigating includes also efforts of opening. Concepts that are taken for granted, such as the very notion of information technology in my case, can be explored, questioned, transgressed, blurred and opened up. Each of the diffracted stories is specific and unique, with its own actors, context, location and situatedness. But the stories are also connected through ANT, and feminist technology and technoscience studies. Case number one, ‘Discourses and Cracks – A Case Study of Information Technology and Writing Women in a Regional Context ’, is about a project, where questions concerning discourses of information society with a special focus on citizenship are discussed and where global and national politics are translated to local and situated practices. Case number two, ‘Translating and Negotiating Information Technology ’, consists of two main parts. The fi rst one is about a regional library project. The analysis of the project is based on the classical Actor Network Theory (ANT) approach that invites the study of the heterogeneous and negotiable shaping of IT. The second part is about librarians developing web-based services. The analysis is inspired by the later development of ANT (called ANTa in the thesis) in order to include more invisible actors, relations and negotiations. Case number three, ‘Negotiating Information Technology: Politics and Practices of The Public Sector Web Production’, is about work practices of a municipal web developer, through which creation of sociotechnical relations of everyday information technology practices is analysed and also mirrored to national and local IT politics. Case number four, ‘Making e-Government Happen – Everyday Co-Development of Services, Citizenship and Technology’, is presenting the same web developer as in the third case, but now his everyday practices are connected with an expanded and wider circuit of co-constructors of information technology. The text is a co-production of a multidisciplinary research group aiming to describe, analyse and problematise connections when creating practices, where technology and society collaborate. Case number fi ve, ‘Citizenship at the Crossroads of Multiple Layers of Sociotechnical Relations’, enrols technology as an active actor in the construction of citizenship in an IT context in Sweden. The perspective emphasising the active agency of non-humans both enhances and challenges the Scandinavian approach of systems development by suggesting a direction towards a cyborgian approach towards technology design. Case number six, ‘Between Stability and Instability – a Project about e-Democracy ’, takes its point of departure from a small-scale project having as its goal the development of e-democracy in a municipal context. In the text the focus is on the stabilisation processes in shaping the technology (‘e’) and democracy parts of the project. I also discuss what kinds of spaces exist in between (the hyphen in e-democracy) and ask if integration between technology and democracy is possible as a whole. Finally, my intention is to step further into stories and practices not yet existing. Inspired by the French philosopher Michel Serres, I introduce the fi guration of an angel as a cartographer, intermediator and (co-) constructor of sociomaterial relations. Angels are needed to sew the separate fi elds of technology, politics and everyday practices to a rich seamless tapestry. They are the ‘artful integrators’ (Suchman).

  • 9. Essuman, Paa Kwesi
    Entrepreneurial Master Project; Svenska Guldkusten Organic Chocolate.2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Svenska Guldkusten aims to provide value for money in the confectionary industry. Its objective is to provide customers with rich organic chocolate that can be eaten as a source of health and wellbeing. This product will reach markets in South of Sweden, specifically, Blekinge and Skåne.   The business’ purpose is to offer customers 100% certified organic cocoa chocolate. Reaching the customer with the product will be through established chocolate shops, supermarkets, internet, schools (university), sport clubs and shop outlets. The target customer group will be individuals who are connoisseurs of fine food and also give due attention to their physical and mental well being. Specifically the earning class, aged between 22 and 60 who constantly maintain a proper diet and exercise regularly. In being different from the competition, persons who cultivate a discriminating palate for the enjoyment of good food will be the market focus. Health which is seen as the future of the confectionery industry has many prospects, thus the business will center its attention more on health trend customers.   Consumers are seen as the most important drivers behind the health and wellness market in terms of food products thus it will be very important if the business market opportunity is based on authorized health claims, marketing, taste of the consumers and the scientific documentation of food products. The business also seeks to supply blocks of chocolates to chocolatiers as way to get to the take off stage.

    The market dynamics of the confectionery industry is one that is moving toward healthiness and organic products. Svenska Guldkusten’s strategy to be sustainable is to stay invaluable to the customer, stay cheap and healthy. In maintaining a position in the consumers mind, innovative ways of spreading the organic food products message will be employed. For instance the catch phrase “Buy a chocolate bar and by life for yourself and a loved one” will be in harness. In carving out a market share for the business, Svenska Guldkusten intends to use cheaper and convenient ways to market the product and also stay health and wellness related.

    The business’ idea is to make a product offer categorized both in branded terms and consumer terms. This will easily communicate information about the product to the grassroots of the target market. Keeping the customers will be through customer co-creation where customer suggestions are seen as important inputs to the product development. This will also create a consistently useful and valuable product for the customer. Strong branding (backed by history), the delivery of rich confection of organic cocoa and pricing will make the business prominent, sustainable and competitive because the source of the import (Ghana) is rich in premium cocoa beans and Sweden has the devotees of refined sumptuous food.

  • 10.
    Fei, Shenyang
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering.
    Development of a general acoustic model for an arbitrary surveillance camera design2018Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis studies how the mechanical design of a surveillance camera affects the acoustic performance, mainly in terms of the frequency response within the human hearing range. During the project, the mechanical characteristics that affect frequency response were investigated by measuring the camera’s audio behavior in an anechoic chamber. A theoretical and adaptable acoustic model was built in COMSOL to simulate the frequency response of the sound path. Measurement and simulation results were compared to identify critical aspects of the mechanical design and adjust accordingly for better acoustic performance.

  • 11. Fredriksson, Martin
    Online engineering: On the nature of open computational systems.2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Computing has evolved from isolated machines, providing calculative support of applications, toward communication networks that provide functional support to groups of people and embedded systems. Perhaps, one of the most compelling feature and benefit of computers is their overwhelming computing efficiency. Today, we conceive distributed computational systems of an ever-increasing sophistication, which we then apply in various settings – critical support functions of our society just to name one important application area. The spread and impact of computing, in terms of so-called information society technologies, has obviously gained a very high momentum over the years and today it delivers a technology that our societies have come to depend on. To this end, concerns related to our acceptance of qualities of computing, e.g., dependability, are increasingly emphasized by users as well as vendors. An indication of this increased focus on dependability is found in contemporary efforts of mitigating the effects from systemic failures in critical infrastructures, e.g., energy distribution, resource logistics, and financial transactions. As such, the dependable function of these infrastructures is governed by means of more or less autonomic computing systems that interact with cognitive human agents. However, due to intricate system dependencies as well as being situated in our physical environment, even the slightest – unanticipated – perturbation in one of these embedded systems can result in degradations or catastrophic failures of our society. We argue that this contemporary problem of computing mainly is due to our own difficulties in modeling and engineering the involved system complexities in an understandable manner. Consequently, we have to provide support for dependable computing systems by means of new methodologies of systems engineering. From a historical perspective, computing has evolved, from being supportive of quite well defined and understood tasks of algorithmic computations, into a disruptive technology that enables and forces change upon organizations as well as our society at large. In effect, a major challenge of contemporary computing is to understand, predict, and harness the involved systems’ increasing complexity in terms of constituents, dependencies, and interactions – turning them into dependable systems. In this thesis, we therefore introduce a model of open computational systems, as the means to convey these systems’ factual behavior in realistic situations, but also in order to facilitate our own understanding of how to monitor and control their complex interdependencies. Moreover, since the critical variables that govern these complex systems’ qualitative behavior can be of a very elusive nature, we also introduce a method of online engineering, whereby cognitive agents – human and software – can instrument these open computational systems according to their own subjective and temporal understanding of some complex situation at hand.

  • 12.
    Ghandchi, Bahram
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Applied Signal Processing.
    Saleh, Taha
    Blekinge Institute of Technology, Faculty of Engineering, Department of Applied Signal Processing.
    Indoor Mobile Positioning system (MPS) classification in different wireless technology domain2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The main purpose of this thesis work is to find and compare different network characteristics of MPS (Mobile Positioning System) in the different wireless technology domains. Since decades ago MNO’s (Mobile Network Operators) added many new services based on the geographical areas of subscribers and their needs. Here we define wireless networks and go through different types of technologies and do the comparison when they collect different types of data for their location-based services and see if we could have the same accuracy with 2G (second generation) of mobile network as like as 3G (third generation) and higher. Finally, we will come up with a proposal for new age technology.

  • 13. Gislén, Ylva
    Rum för handling. Kollaborativt berättande i digitala medier2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [sv]

    Avhandlingen fokuserar på kollaborativt berättande i digitala medier, och tar avstamp i relativt detaljerade beskrivningar av de designprojekt som utgör avhandlingsarbetets ryggrad. Kännetecknande för dessa designprojekt är att de kombinerar fysiska och virtuella rum och/eller flera medieplattformar. Utifrån kritiska läsningar av designval och bruk av de koncept och prototyper som designprojekten utmynnat i presenteras argument för föreslagna "sätt att se" på design av berättande i digitala medier och centrala kvaliteter i miljöer för kollaborativt berättande. Grundläggande är att se berättande som en överenskommelse, som måste springa ur den berättarsituation, den fysiska och sociala verklighet, som utgör en oavvislig del av allt berättande. Denna överenskommelse upprättar ett "rum" för att undersöka och värdera möjlig mänsklig handling, ett rum vars estetiska egenskaper inte kan skiljas från de etiska och politiska frågeställningar som sätts i rörelse av allt berättande. Utifrån detta grundläggande synsätt diskuteras frågan om utformandet av handlingsutrymme i relation till interaktivitet i digitala medier, begrepp som roll, karaktär, samarbete och konflikt samt rytm, poesi och mångtydighet. Argumenten och resonemangen grundas, utöver i den kritiska läsningen av designprojekten, också i en bredare översikt av narrativitetsbegreppets utveckling inom human- och samhällsvetenskaperna de senaste två decennierna samt i en diskussion av teorier, synsätt och vanliga grundantaganden kring berättande i digitala media. Utrymme i avhandlingen ges också åt en kunskapsteoretisk diskussion kring frågan om design som forskning, främst ur ett perspektiv grundat i STS-fältet men också i relation till förda resonemang ifråga om praxisbaserad forskning i allmänhet och designforskning och designteori i synnerhet.

  • 14. Grbic, Nedelko
    Optimal and Adaptive Subband Beamforming2001Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The increased use of personal communication devices, personal computers and wireless cellular telephones enables the development of new inter-personal communication systems. The merge between computers and telephony technologies brings up the demand for convenient hands-free communications. In such systems the users wish to lead a conversation in much the same way as in a normal person-to-person conversation. The advantages of hands-free telephones are safety, convenience and greater flexibility. In many countries and regions, hand held telephony in cars is prohibited by legislation. By placing the microphone far away from the user a number of disadvantages are introduced, which results in substantial speech distortion and poor sound quality. These disturbances are mainly caused by room reverberation and background noise. Furthermore, acoustic feedback generated at the near-end side is a problem for the far-end side talker, who will hear his/her own voice echoed with 100-200 ms delay, making speech conversation substantially more difficult. Digital filtering may be used to obtain a similar sound quality as for hand held telephony. Three major tasks must be addressed in order to improve the quality of hands-free communication systems; noise suppression, room reverberation suppression, and acoustic feedback cancellation of the hands-free loudspeaker. The filtering operation must perform the above mentioned tasks without causing severe near-end speech distortion. A properly designed broad-band microphone array is able to perform all the given tasks, i.e. speech enhancement, echo cancellation and reverberation suppression, in a concise and effective manner. This is due to the fact that the spatial domain may be utilized as well as the temporal domain. This thesis deals with the problem of specification and design of beamformers used to extract the source signal information. A new subband adaptive beamforming algorithm is proposed, where many of the drawbacks embedded in conventional adaptive beamforming are eliminated. Evaluation in a car hands-free situation show the benefits of the proposed method. Blind signal separation is discussed and a new structure based on frequency domain inverse channel identification and time domain separation, is proposed. Further, filter-bank properties and design are discussed together with performance limitations in subband beamforming structures.

  • 15. Gustafsson, Harald
    Speech enhancement for mobile communications2002Doctoral thesis, comprehensive summary (Other academic)
  • 16. Häggander, Daniel
    Software Design Conflicts: Maintainability versus Performance and Availability2001Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A major goal in software engineering is to reduce the cost of maintaining software systems. Finding design methods which make software more easily maintainable has thus been one of the most prioritized challenges during the past decade. While mainstream software design has concentrated on maintainability, other software disciplines e.g. high-performance computing and high-availability systems, have developed other design methods which primarily support the quality attributes that are more important in their areas. More recently, demands have been made for high performance and high availability in typical mainstream software. At the same time, traditional high-performance and high-availability systems tend to incorporate more advanced business functionality, i.e. different software disciplines have started to converge. The situation is not unproblematic since the software design methods developed for achieving performance and availability may have been developed with a limited influence from maintainability, and vice versa. It is thus important to identify and analyze emerging design conflicts. In this thesis I have studied conflicts between maintainability design methods onthe one hand, and performance and availability methods and techniques on the other. I present the results of four case-studies involving four different applications. It is a characteristic of these applications that half of the system can be regarded as a telecommunications system and the other as a typical main-stream system, i.e. all systems make high demands on performance and availability but also very high demands on high maintainability. In studying these applications, I have identified two major conflicts: granularity in dynamic memory usage and source code size. My results show that these two conflicts can cause problems of such amplitude that some applications become unusable. I found that conflicts in certain situations are inherent; in other cases they can be avoided - or at least reduced - by adjusting the design methods used. I have also shown that conflicts may quite simply be a matter of misconceptions. Ten guidelines have been combined into a simple process with the aim of helping software designers to avoid and reduce conflicts. A method which automatically reduces the dynamic memory conflict in object-oriented applications written in C++ has been developed, implemented and evaluated. Finally, I have defined optimal recovery schemes for high availability clusters.

  • 17. Johansson, Martin
    Participatory inquiry: Collaborative Design2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This dissertation focuses on design sessions in which users and stakeholders participate. It demonstrates how material from field studies can be used in exploratory design sessions. The emphasis is on the staging and realization of experiments with ‘possible futures’. Using a design perspective I have worked with how field studies can contribute to design processes in which many parties collaborate. With a starting point in collaborative ‘sketching’ and creation of scenarios I have striven to create a meaningful way for design teams to adopt a practice perspective. The dissertation shows that there need not be any opposition between exploring ‘what is’ and envisioning ‘what can be’. The increase of computer technology in everyday life and the development making information technology become an integrated part of more and more everyday products has given rise to a need to find new ways of working in the process of designing. If it was ever possible to work in an isolated way on either digital or physical technology, this is no longer the case since development requires collaboration over these borders. In the same way, IT plays an increasing significant role in people’s everyday lives. User focus and user involvement have become commonplace. This calls for new ways of organizing the design process. The present dissertation meets this problem. I have participated in four projects in which exploring users everyday practices has become a meaningful design activity and a foundation for collaboration. The purpose of this dissertation is to shed light on the possibilities and the advantages offered by working design oriented with material from field studies. Furthermore, it strives to show how design sessions can be organized and carried out on a practical level and exemplifies with concrete projects. Special emphasis is given to the creation of and the inquiry into design material and the development and use of design games.

  • 18. Johansson, Stefan J.
    On Coordination in Multi-agent Systems2002Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Agent technology enables the designers of computer based systems to construct software agents that are able to model attitudes. We present a frame-work in which these artifacts aim to express the preferences of both their designers and their owners. Just like human societies need rules, regula-tions, norms and social laws, in order to function, societies of agents need coordination mechanisms in order to work efficiently. We show why some higher level goals of agents are incompatible, e.g. the automatic creation of coalitions among agents, and at the same time being self-interested and boundedly rational. One way to model the outcome of planned interactions between agents is to apply game theory. We use game theory for proving some results, e.g. a \No free lunch" theorem. For more practical applications, however, other approaches are often needed. One such domain is dynamic resource allocation, where agents through auction mechanisms or different kinds of mobile broker techniques solve the problem of coordinating the allocation. We present comparisons of the results of simulations of several of these approaches in a telecommunication networks application. Another interesting domain concerns mobile robots for playing soccer. To model this problem, a novel approach called artificial electrical fields, is used for both navigation and manipulation of objects.

  • 19. Johansson, Sven
    Active Control of Propeller-Induced Noise in Aircraft: Algorithms & Methods2000Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the last decade acoustic noise has become more and more regarded as a problem. In cars, boats, trains and aircraft, low-frequency noise reduces comfort. Lightweight materials and more powerful engines are used in high-speed vehicles, resulting in a general increase in interior noise levels. Low-frequency noise is annoying and during periods of long exposure it causes fatigue and discomfort. The masking effect which low-frequency noise has on speech reduces speech intelligibility. Low-frequency noise is sought to be attenuated in a wide range of applications in order to improve comfort and speech intelligibility. The use of conventional passive methods to attenuate low-frequency noise is often impractical since considerable bulk and weight are required; in transportation large weight is associated with high fuel consumption. In order to overcome the problems of ineffective passive suppression of low-frequency noise, the technique of active noise control has become of considerable interest. The fundamental principle of active noise control is based on secondary sources producing ``anti-noise.'' Destructive interference between the generated and the primary sound fields results in noise attenuation. Active noise control systems significantly increase the capacity for attenuating low-frequency noise without major increase in volume and weight. This doctoral dissertation deals with the topic of active noise control within the passenger cabin in aircraft, and within headsets. The work focuses on methods, controller structures and adaptive algorithms for attenuating tonal low-frequency noise produced by synchronized or moderately synchronized propellers generating beating sound fields. The control algorithm is a central part of an active noise control system. A multiple-reference feedforward controller based on the novel actuator-individual normalized Filtered-X Least-Mean-Squares algorithm is introduced, yielding significant attenuation of such period noise. This algorithm is of the LMS-type, and owing to the novel normalization it can also be regarded as a Newton-type algorithm. The new algorithm combines low computational complexity with high performance. For that reason the algorithm is suitable for use in systems with a large number of control sources and control sensors in order to reduce the computional power required by the control system. The computational power of the DSP hardware is limited, and therefore algorithms with high computational complexity allow fewer control sources and sensors to be used, often with reduced noise attenuation as a result. In applications, such as controlling aircraft cabin noise, where a large multiple-channel system is needed to control the relative complex interior sound field, it is of great importance to keep down the computational complexity of the algorithm so that a large number of loudspeakers and microphones can be used. The dissertation presents theoretical work, off-line computer experiments and practical real-time experiments using the actuator-individual normalized algorithm. The computer experiments are principally based on real-life cabin noise data recorded during flight in a twin-engine propeller aircraft and in a helicopter. The practical experiments were carried out in a full-scale fuselage section from a propeller aircraft.

  • 20. Jönsson, Anders
    Lean Prototyping of Multi-body and Mechatronic Systems2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Major drivers behind increased efforts in product development are the increased competition due to globalisation and the urgent transformation of society towards sustainability. Furthermore, the average product lifetime has been compressed significantly over the last decade. Due to these trends, there is increasing demand for an efficient product development process. Cutting time-to-market, reducing costs and increasing quality are widely accepted as key factors to successful product development. Consideration of sustainability aspects in product development is also becoming increasingly important. Methods and tools that are useful also for small and medium sized enterprises are of particular importance for the Swedish industry. This thesis suggests a definition of lean prototyping and points to its potential for supporting efficient product development. This is done through two case studies: a soil compactor machine treated as a multi-body system and a water jet cutting machine treated as a mechatronic system. Lean prototyping is defined as a coordinated approach to experimentation with the purpose of achieving cost-efficient and accurate enough prediction of product characteristics to support optimisation and well-informed design decisions during product development, especially in the early stages. This often involves an iterative search for and use of a suitable combination of virtual and limited physical prototypes as well as the reuse of knowledge from previous projects. The case studies are performed in cooperation with one small and one medium sized company, indicating the usefulness of the approach for different product types as well as for different company sizes. More specifically, the validated multi-body model of the soil compactor machine describes the dynamics of the machine satisfactorily and the optimisation study shows a significant potential for improved compaction capacity. This potential would not likely been found through traditional physical prototyping. The related comparative study of contact transition conditions is a contribution to consistent impact modelling in multi-body dynamics in general. The real-time virtual machine concept for simulation of the water jet cutting machine, including detailed mechanical component models, is unique. The fully automated concept implementation makes it a promising base for multidisciplinary design optimisation of the water jet cutting machine, and probably of mechatronic products in general.

  • 21. Kao-Walter, Sharon
    On the Fracture of Thin Laminates2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis concerns mechanical and fracture properties of a thin aluminium foil and polymer laminate that is widely used as packaging material. The possibility of controlling the path of the growing crack propagation by adjustment of the adhesion level and the property of the polymer layer is investigated. First, the fracture process of the aluminium foil is investigated experimentally. It is found that fracture occurs at a much lower load than what is suggested by standard handbook fracture toughness. Observations in a scanning electron microscope with a tensile stage show that small-scale stable crack growth occurs before the stress intensity factor reaches its maximum. An examination using an optical profilometric method shows almost no plastic deformation except for in a small necking region at the crack tip. However, accurate predictions of the maximum load are obtained using a strip yield model with a geometric correction. Secondly, the mechanical and fracture properties of the laminate are studied. A theory for the mechanics of the composite material is used to evaluate a series of experiments. Each of the layers forming the laminate is first tested separately. The results are analysed and compared with the test results of the entire laminate with varied adhesion. The results show that tensile strength and strain at peak stress of the laminate, with or without a crack, increase when the adhesion of the adhesive increases. It is also found that a much larger amount of energy is consumed in the laminated material at tension compare with the single layers. Possible explanations for the much higher toughness of the laminate are discussed. Finally, the behaviour of a crack in one of the layers, perpendicular to the bimaterial interface in a finite solid, is studied by formulating a dislocation superposition method. The stress field is investigated in detail and a so-called T stress effect is considered. Furthermore, the crack tip driving forces are computed numerically. The results show that the analytical methods for an asymptotically small crack extension can also be applied for a fairly large amount of crack growth. By comparing the crack tip driving force of the crack deflected into the interface with that of the crack penetrating into the polymer layer, it is shown how the path of the crack can be controlled by selecting a proper adhesion level of the interface for different material combinations of the laminate.

  • 22. Mattsson, Michael
    Evolution and Composition of Object-Oriented Frameworks2000Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis comprises studies of evolution and composition of object-oriented frameworks, a certain kind of reusable asset. An object-oriented framework is a set of classes that embodies an abstract design for solutions to a family of related problems. The work presented is based on and has its origin in industrial contexts where object-oriented frameworks have been developed, used, evolved and managed. Thus, the results are based on empirical observations. Both qualitative and quantitative approaches have been used in the studies performed which cover both technical and managerial aspects of object-oriented framework technology. Historically, object-oriented frameworks are large monolithic assets which require several design iterations and are therefore costly to develop. With the requirement of building larger applications, software engineers have started to compose multiple frameworks, thereby encountering a number of problems. Five common framework composition problems, together with existing solution approaches and the underlying causes for the problems are presented in this thesis. Adopting a reuse technology, such as object-oriented frameworks, in a software development organization causes changes and additions of practices and procedures. We present problems and possible solutions related to these issues. Examples of topics addressed are; domain scoping, business models, verification of the framework’s abstract behavior, and when to release a framework. Object-oriented frameworks, as all software, evolve due to changed and new requirements. The evolution of object-oriented framework can be more costly than conventional software since there generally exist several applications based on and forced to evolve with the framework. In our studies, we characterize different views of framework evolution. Aspects investigated are structural and behavioral stability, change and growth rates using historical information and effort distribution of framework development and customization. We also provide an assessment of the methods used for characterizing the evolution against the following management issues; identification of evolution-prone modules, framework deployment, change impact analysis, benchmarking and requirements management. As part of these studies, we have extended and validated two proposed methods for software evolution; one for quantitatively assessing stability of a framework, which has been extended with a set of framework stability indicators, and one for identifying evolution-prone modules based on historical information (adapted for object-orientation). Our studies have validated that these methods are feasible and possible to apply on industrial object-oriented frameworks. In addition, we provide quantitative evidence that the use of framework technology reduces application development effort.

  • 23. Nilsson, Monica E
    Transformation through Integration2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Abstract This study analyzes an attempt at integration of a pre-school class, a leisure-time center and an elementary school in Sweden. The integration was organized in the form of Vertical Track which implies a successive development of groups comprising children between six and twelve years old, pre-school teachers, recreation pedagogues, and schoolteachers. The integration was prompted by state governed reforms such as the 1992 law allowing six-year olds to start compulsory school. The study is based on cultural-historical activity theory and was carried out as participant observation and action research. The study addresses the question of the potentials and alternative goals for change and development of the present school pedagogy and classroom practice that integration implies. Special attention has been paid to what tools might potentially mediate in processes of integration. A research and educational program, the 5thD, was jointly created between researchers and teachers and located in a Vertical Track. The capacity of this complex tool as a mediator in the multicultural Vertical Track structure was explored. It is argued that the Vertical Track as an instantiation of the integration reform represents an arena for potential expansive transformation. However, in order for integration to have an impact on the pedagogical practice in schools, teacher interactions need to be mediated by communicative and conceptual tools. It is suggested that the 5thD program is an example of such tools. Keywords: Integration, pre-school teacher, recreation pedagogue, schoolteacher, contradiction, expansive learning, mediation, and tool.

  • 24. Nordberg, Jörgen
    Signal Enhancement in Wireless Communications Systems2002Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Digital Wireless communications has been one of the fastest growing communication techniques during the last decade. Today there exists several different communication systems that use wireless techniques. They share one common property that they transmit data through a radio interface. The radio channel is a tough channel that will both distort and disturb the transmitted signal in various ways. In Jörgen Nordberg's PhD-thesis "Signal Enhancement in Wireless Communications Systems" several different signal enhancement schemes are presented. They have the objective to minimize the impact of the channel. The main part of this thesis presents work on interference cancellation, i.e. how to reduce the impact of other interfering signals on the channel of interest. This is achieved by utilizing the spatial domain, i.e. the receiver is using several antennas to receive the transmitted signals. By using a multitude of antennas techniques like spatial diversity, adaptive antenna arrays, signal separation and beamforming can be applied to combat the interfering signals. In the single antenna case there is often a need to do channel equalization. Since, channel equalization is an inverse filtering, it will often result in estimation of equalization filter parameters of very high order. To reduce the both the complexity and improve the convergence speed of the equalization filter parameter estimation subband processing techniques can be used. In this case the received signal is separated up into different frequency bands (subbands) and decimated according to the bandwidth of the signal. The channel equalization problem is then solved for each subband at a lower sampling rate. Hence, the channel equalization problem is transformed from estimating the parameters of a high order filter into estimating several filter of much lower order.

  • 25. Persson, Per
    Annealing Based Optimization Methods for Signal Processing Applications2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, a class of combinatorial optimization methods rooted in statistical mechanics and their use in signal processing applications will be discussed. The thesis consists of two separate parts. The first part deals with the rationale for my work and also covers the background information necessary to put the second part, which consists of a number of papers, in context. There are (at least) two sides to an optimization problem---the problem statement arising from an application or a design and the selection of an algorithm to solve the problem. In this work the problem statements are practical problems, of combinatorial nature, frequently encountered in signal processing and the algorithms of choice are annealing based algorithms, founded in statistical mechanics. From my work, it is my experience that solving a particular problem often leads to new developments on the part of the algorithm which, in turn, open up possibilities to apply the modified algorithm to a new set of problems, leading to a continuously improving algorithm and a growing field of applications. The included papers deal with the application of annealing optimization methods to the problems of configuring active noise and vibration control systems, digital filter design and adaptive filtering. They also describe the successive development of a highly efficient entropy-directed deterministic annealing (EDDA) optimization algorithm detailed in the final paper.

  • 26. Rydhagen, Birgitta
    Feminist Sanitary Engineering as a Participatory Alternative in South Africa and Sweden2002Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The main theme in this thesis is potentials for increased user participation in the development of ecological sanitation technologies. The argument is that ecological sanitary engineering can be regarded as a heterogeneous practice that needs to incorporate environmental considerations as well as users’ knowledges and aspirations. To be a heterogeneous engineer therefore means to acquire skills for advanced dialogue with the users and other stakeholders, rather than providing finished technical solutions. In a case study in rural South Africa, I found that much of the responsibility for taking initiatives for the transformation of the water supply and sanitation systems lies with the community. By contrast, a case study of ecological sanitation in urban Sweden revealed that there was generally very little room for user involvement; instead, sanitation specialists presented a picture of the users as recipients of technical systems and information. These two different cases form the basis for a discussion about the relationship between users and specialists and pose the question of how we can encourage participatory technology development practices that users, specialists and ecosystems can endure. On the basis of feminist theory, technoscience and participatory methodologies, I have identified some criteria for feminist sanitary engineering. These include recognition of diversity, feminism beyond gender/deep feminism, reflectivity and heterogeneous engineering, and action research and user participation. The transformation of sanitary engineering towards the inclusion of these criteria is a long-term process, which needs to begin with reflection among sanitation specialists.

  • 27. Rönkkö, Kari
    Making Methods Work in Software Engineering: Method Deployment - as a Social Achievement2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The software engineering community is concerned with improvements in existing methods and development of new and better methods. The research approaches applied to take on this challenge have hitherto focused heavily on the formal and specifying aspect of the method. This has been done for good reasons, because formalizations are the means in software projects to predict, plan, and regulate the development efforts. As formalizations have been successfully developed new challenges have been recognized. The human and social role in software development has been identified as the next area that needs to be addressed. Organizational problems need to be solved if continued progress is to be made in the field. The social element is today a little explored area in software engineering. Following with the increased interest in the social element it has been identified a need of new research approaches suitable for the study of human behaviour. The one sided focus on formalizations has had the consequence that concepts and explanation models available in the community are one sided related in method discourses. Definition of method is little explored in the software engineering community. In relation to identified definitions of method the social appears to blurring. Today the software engineering community lacks powerful concepts and explanation models explaining the social element. This thesis approaches the understanding of the social element in software engineering by applying ethnomethodologically informed ethnography and ethnography. It is demonstrated how the ethnographic inquiry contributes to software engineering. Ethnography is also combined with an industrial cooperative method development approach. The results presented demonstrate how industrial external and internal socio political contingencies both hindered a method implementation, as well as solved what the method was targeted to do. It is also presented how project members’ method deployment - as a social achievement is played out in practice. In relation to this latter contribution it is provided a conceptual apparatus and explanation model borrowed from social science, The Documentary method of interpretation. This model addresses core features in the social element from a natural language point of view that is of importance in method engineering. This model provides a coherent complement to an existing method definition emphasizing formalizations. This explanation model has also constituted the underpinning in research methodology that made possible the concrete study results.

  • 28. Sokoler, Tomas
    Going Beyond the Desktop Computer with an Attitude2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This dissertation is based upon the work within a number of research projects, five of which are presented in detail. The work follows the direction of research laid out by the Ubiquitous Computing and Augmented Reality research programs and concerns the broad question of where to go as we seek to take digital technology, and human interactions with this technology, beyond the traditional desktop computer. The work presented takes a design-oriented approach to Human Computer Interaction research. Five prototype systems are presented: Ambient displays for remote awareness, a navigation device providing guidance through tactile cues, a personal device for wastewater plant operators, paper cards enabling control of video playback, and a cell phone that enables you to ‘talk silent’. It is discussed how these prototypes, despite obvious differences, all reflect the same overall attitude towards the role of digital technology. It is an attitude emphasizing that integration of digital technology with everyday human activities means making computational power manifest as part of a larger patchwork of resources. Furthermore, it is an attitude promoting the design of digital technology that leaves the control and initiative with people and their earned ability to take appropriate action when faced with the particularities of the social and physical settings encountered in everyday life beyond the computer screen. In other words, this dissertation brings forward, by using five prototypes as examples, an attitude that encourages us to recognize, embrace, and take advantage of, the fact that human interaction with digital technology takes place, not in a vacuum, but in a rich and diverse world full of many resources for human action other than the digital technology we bring about.

  • 29. Sutter, Berthel
    Instruction at heart. Activity-theoretical studies of learning and development in coronary clinical work2002Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The aim of the thesis is to study the role of instruction in the interconnection of instruction-learning-development. The thesis consists of six empirical papers and a summing-up and perspectivizing introductory paper. Five of the empirical studies concern so called heart conferences, clinical diagnostic meetings, which at the time of my study, 1995-1996, were arranged as telemediated conferences between a sub-team of surgeons and radiologists in a university clinic, and a sub-team of cardiologists and radiologists in a regional hospital. The outcome of the coronary diagnostic work in the heart conferences was patient diagnoses and decided-upon treatment (surgery, balloon dilatation, or conservative treatment). The sixth empirical study, conducted in the autumn 2000, investigates the design and redesign of a central artifact used in the heart conference, ?the angio film,? produced in the angio lab. A recurrent theme in the empirical papers is whether artifacts might be instructive and, if so, in what ways. The introductory paper is a hybrid between an ordinary summing-up paper of the findings in the empirical studies, and a perspectivizing presentation of activity-theoretical approaches to instruction, learning and development, elaborating on three basic aspects (learning as a collaborative phenomenon, the instructiveness of artifacts, and the relation between learning and development on an individual level, but primarily on an activity level). In conclusion, my study outlines an approach to learning based on new perspectives on instruction.

  • 30. Svahnberg, Mikael
    Supporting Software Architecture Evolution2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Today it is more a rule than an exception that software systems have a lifecycle of more than several years. Hence, software evolution is inevitable. During the life span of a software system the domain in which the system is working evolves and changes. This causes changes to the software system, and the software system may also be evolved to satisfy new markets. The ability to evolve gracefully, and thus the long-term success of a software system, is to a large extent governed by its software architecture and the ability of the software architecture to fulfil requirements on quality attributes and to adapt to evolving requirements. In this thesis we study evolution of software architectures and what can be done to support this evolution. We focus on three particular aspects of evolution support: how to ensure that the correct blend of quality attributes is met (architecture selection), the technical means available for supporting changes in the software system (variability), and what types of changes that are likely to occur during evolution (categories of evolution). We introduce a method for architecture evaluation and selection that focus on ensuring that the selected software architecture is the architecture candidate with the most potential for fulfilling a particular blend of quality attributes. The method is based on quantification of expert opinions and focused discussions where these expert opinions differ. The architecture evaluation and selection method is studied in both an academic and in an industry setting. We also introduce a taxonomy of techniques for realising variability in a software system and study how the techniques in this taxonomy are applied in different evolution situations. The taxonomy is based on several industry case studies. Two industry cases are studied in further detail and the evolution of these systems are followed over a number of releases and generations. During this evolution it is shown how variability mechanisms are used to also support evolution, and that there are typical cases of evolution that a software system can be prepared to cope with. The contribution of this thesis is that it increases the understanding of how evolution occurs in a software system, how to create software that is flexible enough to support evolution and how to evaluate and select a software architecture that meets a particular blend of quality attributes. Together this ensures that a software system is based on a software architecture that fits the current quality requirements and that is flexible in the right places so that it is able to evolve gracefully.

  • 31. Søilen, Klaus Solberg
    Wirtschaftsspionage in Verhandlungen aus Informationsökonomischer und Wirtschaftsetischer Perspektive: eine Interdisziplinäre Analyse2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The dissertation examines a case of industrial espionage by one of the parties involved in a forthcoming international negotiation. We want to know what consequences a burglary has for the actual negotiation. The dissertation consist of five hypothesis, of which the three first were empirically tested. The discussion of thesis four and five is supported basically by research literature, but have also found indirect support in the empirical study. A game theoretical model of four information sets is used. Thesis 1: Pay-offs do not change significantly from one information set to the other. confirmed Thesis 2: Behavior do not change significantly from one information set to the other. confirmed Thesis 3: The perception of fairness do not change significantly from one information set to the other. confirmed Thesis 4: International negotiations is socially so complex that it only makes sense to study the phenomena from an interdisciplinary angle. confirmed Thesis 5: A descriptive evolutionary approach can be an alternative to neoclassical economic theory in understanding the study of international negotiations. confirmed The study also confirms that economic theory is correct in excluding the ethical dimension from their models, as these factors have little influence on the end price. Fairness plays only a minor role in international negotiations. **

  • 32. Tap, Hans
    Accountable interaction. Exploring interactional features of technology in use2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Today we have computers in all kind of work places, and it is a fairly common artefact in many homes. What becomes an interesting topic when computers end up in everyday occasions and used by people who are not necessarily computer experts is how the user interface should be designed to be rendered practically useful. This thesis explores part of this problem by looking into the details of how we use technology and artifacts in our everyday activities and utilizes the insights for developing design concepts. Of particular interest is concept development for user interfaces that goes beyond the traditional desktop computer setup with a screen, keyboard and mouse as tools for interaction. The work relies on an ethnographic approach to get an understanding of moment-by-moment use of technology. Fields like Ubiquitous Computing and Computer Supported Cooperative Work are great sources for inspiration when it comes both to theoretical insights and visions about future use of computers.

  • 33. Winberg, Mathias
    Noise and Vibration Control of Combustion Engine Vehicles2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Noise and vibrations have over the last two decades been regarded as significant environmental health problems. Regulations regarding acoustic as well as vibration levels have therefore become more stringent. This thesis embraces two different techniques to reduce unwanted noise and vibrations, spectral subtraction and active noise and vibration control. The applications treated for noise and vibration problems are mainly means of transportation driven by combustion engines as for example, helicopters, boats, and cars. All these vehicles have low-frequency noise and vibration problems which are difficult to solve by means of passive isolation, hence alternative methods must be sought. Two different scenarios are studied. First, the high noise level in the interior of the vehicle is accepted and the humans inside are equipped with headsets utilizing both passive as well as active noise control. If the means of transportation employs some kind of communication equipment, such as for a cellular telephone or an intercom radio, the noisy speech signal picked up by the microphone is cleansed by spectral subtraction, which is a non-linear filtering method employed in the frequency domain. In the second scenario the entire interior of the vehicle is subjected to noise and vibration reduction by means of active noise and vibration control. Active noise and vibration control is the art of reducing a primary sound or vibration field by interference with a secondary anti-field. The thesis focus on real-life applications which implies that a lot of measurements and practical difficulties must be treated for both scenarios, especially in the area of active noise and vibration control. In this area, the basic idea seems straight-forward, but implementing it in large and complex structures, such as vehicles, is extremely difficult, in particular if high attenuation is required.

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