The semiconductor technology has enabled the fabrication of integrated circuits (ICs), which may include billions of transistors and can contain all necessary electronic circuitry for a complete system, so-called System-on-Chip (SOC). In order to handle design complexity and to meet short time-to-market requirements, it is increasingly common to make use of a modular design approach where an SOC is composed of pre-designed and pre-verified blocks of logic, called cores. Due to imperfections in the fabrication process, each IC must be individually tested. A major problem is that the cost of test is increasing and is becoming a dominating part of the overall manufacturing cost. The cost of test is strongly related to the increasing test-data volumes, which lead to longer test application times and larger tester memory requirement. For ICs designed in a modular fashion, the high test cost can be addressed by adequate test planning, which includes test-architecture design, test scheduling, test-data compression, and test sharing techniques. In this thesis, we analyze and explore several design and optimization problems related to core-based SOC test planning. We perform optimization of test sharing and test-data compression. We explore the impact of test compression techniques on test application time and compression ratio. We make use of analysis to explore the optimization of test sharing and test-data compression in conjunction with test-architecture design and test scheduling. Extensive experiments, based on benchmarks and industrial designs, have been performed to demonstrate the significance of our techniques.

This thesis presents a framework for parallelized program analysis. It uses available parallel processing power in standard desktop computers to speed up static program analysis. Today, processor chip manufacturers produce single processor chips containing multiple cores, each with a processing power of previous single-core processors. Major processor suppliers have released processors with 2, 4, and 6 cores and are currently working on processors with 8 and 16 cores, and are expected to produce processors with a few hundred cores in the near future. Static program analysis finds programs’ runtime properties at compile time. It is time-consuming to produce results of high quality, which is necessary for the results to be useful. One way to reduce analysis time is to take advantage of the processing power of multi-core processors. The presented framework supports sequences of static program analyses, each producing partial results. In this thesis, the framework is instantiated with points-to analysis, reachability analysis, and escape analysis. Points-to analysis calculates object references in a program and provides the input for subsequent analyses. Reachability analysis calculates reachable methods and provides further input to the escape analysis, which finds object and method lifetimes. It is possible to implement other data-flow analyses using the same parallelized approach by choosing different analysis value types and transfer functions. The framework also facilitates the implementation of static analyses that automatically benefit from the parallelized approaches that the framework offers. The framework shortens the analysis time for static program analysis based on points-to analysis in two ways: using a parallelized approach for points-to analysis, and using parallelized approaches for analyses relying on points-to analysis results. It is also possible to shorten the development time of other analyses when reusing the functionality of the framework. To further improve the usefulness of the framework, requirements for additional static analysis should be captured, and the framework should be extended accordingly. It should also facilitate to perform independent client analyses in parallel, rather than in sequence. These challenges are part of our future work.

I denna avhandling presenteras resultat inom två områden – elektroniska betalningar och hierarkiska gruppsignaturer. • En starkare säkerhetsdefinition för digitala pengar presenteras med syfte att användare inte ska behöva lita på banken i samma utsträckning som för äldre definitioner. Denna starkare definition ges dels som en experimentbaserad definition och dels som en definition i ramverket för universell sammansättning (UC). Det visas att säkerhet enligt den experimentbaserade definitionen implicerar UC-säkerhet. Dessutom beskrivs en konstruktion med allmänna metoder som är säker enligt den nya definitionen i modellen med gemensam referenssträng (CRS) om den baseras på en familj lönndörrspermutationer. I samband med konstruktionen definieras extraherbara, simuleringssunda, icke-interaktiva kunskapslösa bevis. Existensen av sådana bevis i CRS-modellen bevisas under antagandet att det existerar en familj lönndörrspermutationer. • Ett system för digitala pengar beskrivs. Systemet bygger på symmetriska primitiv och är säkert i UC-ramverket under antagandet att ett symmetriskt CCA2-säkert kryptosystem, ett CMA-säkert signaturssystem och en familj enkelriktade kollisionsfria hashfunktioner används. Beviset är inte i slumporakel-modellen. Tack vare sin höga effektivitet är system väl lämpat för exempelvis smartkort och mobiltelefoner. Det beskrivs vidare hur systemet kan användas som ett system för gruppsignaturer med engångsnycklar. • Begreppet hierarkiska gruppsignaturer introduceras. Detta är en äkta generalisering av gruppsignaturer som tillåter flera gruppchefer organiserade i ett träd med signatörerna som löv. Om en signatör är löv i ett delträd under en gruppchef får denne gruppchef reda på till vilket delträd signatören hör. Definitioner och tre olika konstruktioner ges. Den första konstruktionen använder allmänna metoder och är säker om den baseras på en familj lönndörrspermutationer. Denna konstruktion är inte avsedd för praktisk använding, utan ska ses som ett bevis att definitionen är rimlig. Den andra definitionen är nästan praktisk, och dess säkerhet bevisas i slumporakelmodellen under starka RSA-antagandet och DDH-antagandet. Den tredje konstruktionen är praktisk och säker under starka RSA-antagandet och DDH-antagandet. Denna konstruktion är optimistisk i den meningen att en gruppchef kan behöva interagera med andra parter för att öppna en signatur. Slutligen bevisas att om ett system för hierarkiska gruppsignaturer är säkert så realiserar det en ideal funktionalitet i UC-ramverket. / In this thesis we present results in two areas, electronic cash and hierarchical group signatures. • We investigate definitions of security for previously proposed schemes for electronic cash and strengthen them so that the bank does need to be trusted to the same extent. We give an experiment-based definition for our stronger notion and show that they imply security in the framework for Universal Composability. Finally we propose a scheme secure under our definition in the common reference string (CRS) model if based on a family of trapdoor permutations. As a tool we define and prove the existence of simulation-sound non-interactive zeroknowledge proofs (NIZK-PK) in the CRS-model under the assumption that a family of trapdoor permutations exists. • We propose a scheme for electronic cash based on symmetric primitives. The scheme is secure in the framework for universal composability if based on a symmetric CCA2-secure encryption scheme, a CMA-secure signature scheme, and a family of one-way, collision-free hash functions. In particular, the security proof is not in the random-oracle model. Due to its high efficiency, the scheme is well-suited for devices such as smart-cards and mobile phones. We also show how the proposed scheme can be used as a group signature scheme with one-time keys. • We introduce the notion of hierarchical group signatures. This is a proper generalization of group signatures, which allows multiple group managers organized in a tree with the signers as leaves. For a signer that is a leaf of the subtree of a group manager, the group manager learns which of its children that (perhaps indirectly) manages the signer. We give definitions and three different constructions. Our first construction uses general methods and is secure if based an a family of trapdoor permutations. It is not intended for actual use, but serves as a proof of concept of our definition. Our second construction is almost practical, and we prove its security in the random oracle model under the strong RSA assumption and the DDH assumption. Our third construction is practical and secure under the strong RSA assumption and the DDH assumption in the random oracle model. The third construction is optimistic in that a group manager may need to interact with other parties to open a signature of a corrupt signer. Finally we show that if a hierarchical group signature scheme is secure, then it realizes an ideal hierarchical group signature scheme in the framework for universal composability. / QC 20100923

Software development processes provide means to develop software in a structured and disciplined way. Although these processes provide support for how to develop software, there is still a challenge to successfully apply them in practice. Thus, there is a need to support management of software development processes so that their use generate as good results as possible. The thesis presents support for agile and plan-driven methods, which represent different approaches for developing software. The support for agile methods was developed after performing a case study and a survey, in order to gather empirical data. The support for plan-driven methods was developed after applying a combination of research methods such as a controlled experiment, grounded theory and theoretical analysis. The developed support for managing agile and plan-driven methods is based on the results from an extensive empirical basis consisting of five studies, with both qualitative and quantitative approaches. The developed support for agile methods consists of a set of guidelines for organizations to consider when introducing agile methods. The developed support for plan-driven methods concerns support for the Business Process Analyst role to manage its work in a software development context. Further, the Personal Software Process is allocated to several roles in order to increase its applicability. / QC 20101001

All organizations have an information system. An information system is all that which contribute to the distribution within an organization, and without the information system, the organization would not survive. Despite this, work with changing or constructing information systems often end up with suboptimal results. In recent scientific articles, and within profession-specific newspapers, the figures on how many such project end up as failures range between 70 and 80 percent. One source of problems with information systems work is deficiencies of the governance of the change processes. Further, many methods applied to information systems work are in fact software systems method and may thus be suspected to miss important aspects of the information system. In this thesis I have studied approaches for supporting the information systems development process. These approaches have all included trying to find aspects of the information system and trying to measure, simulate or in other ways asses them in order to get an overview of where effort has to be added in the development process.The results of the thesis include recommendations surrounding the simulations of such aspects, as well as a model where the aspects have been formulated into criteria for information system evaluation. The CISE model (Criteria for Information Systems Evaluation) is the main product, and it is available to useas a checklist during information systems work. / Alla organisationer har ett informationssystem. Ett informationsystem är allt det som inom en organisation bidrar till att sprida information, och utaninformationssystemet skull organisationen inte överleva. Trots detta resulterar arbete med att ändra och bygga informationssystem ofta i resultat som är sämre än önskvärda. I senare vetenskapliga artiklar, och inom den professionella pressen, nämns ofta siffror kring 70-80 procent i samband med hur ofta dessa projekt misslyckas.En källa till problem med informationssystemsarbete är brister i styrningen av förändringsprocesserna. Vidare, många metoder som används för informationssystemsarbete är egentligen metoder avsedda för mjukvaruutveckling, och som därmed kan misstänkas missa viktiga aspekter när de tillämpas på informationssystem. I den här avhandlingen har jag studerat angreppssätt för att stödja informationssystemsutvecklingsprocessen. Dessa angreppssätt satsar alla påatt hitta aspekter av informationsystem, och att försöka mäta, simulera eller i andra former uppskatta aspekterna för att få en översikt över var mer kraft behövs i utvecklingsprocessen. Resultaten av avhandlingen inkluderar rekommendationer kring simulering av sådana aspekter, samt en model där aspekterna formulerats som kriterierför utvärdering av informationssystem. CISE-modellen (Criteria for InformationSystems Evaluation) är den främsta produkten av avhandlingen, och den gåratt använda som en checklista under informationssystemsarbete.

To evaluate libraries for continuous speech recognition, a test based on TED-talk videos was created. The different speech recognition libraries PocketSphinx, Dragon NaturallySpeaking and Microsoft Speech API were part of the evaluation. From the words that the libraries recognized, Word Error Rate (WER) was calculated and the results show that Microsoft SAPI performed worst with a WER of 60.8%, PocketSphinx at second place with 59.9% and Dragon NaturallySpeaking as the best with 42.6%. These results were all achieved with a Real Time Factor (RTF) of less than 1.0. PocketSphinx was chosen as the best candidate for the intended system on the basis that it is open-source, free and would be a better match to the system. By modifying the language model and dictionary to closer resemble typical TED-talk contents, it was also possible to improve the WER for PocketSphinx to a value of 39.5%, however with the cost of RTF which passed the 1.0 limit,making it less useful for live video.

Within each web service there is a bottleneck which limits the maximum throughput. In this thesis the bottleneck of the media web service is in the task of transcoding. We explore the option of creating new transcoding nodes on-demand to deal with the computationally expensive task of video transcoding. The thesis presents a prototype for controlling the expansion of a transcoding service into the cloud. Using cloud infrastructure-as-a-service allows for creation of new nodes, without any modication to the software and via a prototype RESTful API using a simple syntax. The prototype also includes a systems integration framework (Chef) to configure new nodes to run any specified service. Due to licensing issues, we could not install the transcoding software itself while performing system testing. A substitute configuration of software of similar complexity was installed instead, and a large suite of tests shows that a single new node can be fully configured and a host notified about the node's existence within approximately 7 minutes. Updates/configurations can then be pushed out to all existing nodes, or a subset of nodes thereof. The destruction of nodes takes less than a minute and implicitly disassociate the nodes with all related resources, allowing for resource management. The thesis also explores the theoretical possibility of using MapReduce as a distributed model for a video transcoding service. Concepts in cloud computing, virtualization, video compression and transcoding are discussed as a part of an in-depth-study.

Despite the increasing popularity in the academic and practical fields of digital gaming, little has been explored and documented about gaming experience, especially firsthand account. This study uses Bruno Latour’s concept of the Thing while investigating digital gaming experience from frequent gamers’ standpoint using focus groups methodology. Additionally in-depth interviews were conducted with developers in order to gain a business perspective on the status of digital games development with regard to gamers. From the findings, Reality, Game, and Player were identified as agencies and their associations with the experiences of the gamers were gathered in making the Thing about gaming experience a matter of concern providing new meanings and further understandings of the abstract sets of experiences.

Human proximity tracking and human situation inference are exploited for comprehending human interaction with objects in kitchen. The importance of this study is to offer interactive and personalized kitchen environment for elderly and disabled people. Also, this smart environment allows for independent living for elderly and disabled people. This study proposes human proximity tracking and inferring human situation in smart environment. A precision of 100% and a recall of 65.22% were obtained from the result of proximity tracking. The result of precision indicates that human proximity tracking works accurately in kitchen environment. Interms of human situation inference, the result of accuracy of fuzzy logic system was obtained as above 96% precision in each situative space model set, except recognizable set. This result shows that system works well with a few exceptions in relation to human situation inference.

Biologically detailed computational models of large-scale neuronal networks have now become feasible due to the development of increasingly powerful massively parallel supercomputers. We report here about the methodology involved in simulation of very large neuronal networks. Using conductance-based multicompartmental model neurons based on Hodgkin-Huxley formalism, we simulate a neuronal network model of layers II/III of the neocortex. These simulations, the largest of this type ever performed, were made on the Blue Gene/L supercomputer and comprised up to 8 million neurons and 4 billion synapses. Such model sizes correspond to the cortex of a small mammal. After a series of optimization steps, performance measurements show linear scaling behavior both on the Blue Gene/L supercomputer and on a more conventional cluster computer. Results from the simulation of a model based on more abstract formalism, and of considerably larger size, also shows linear scaling behavior on both computer architectures. / <p>QC 20100722</p>