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This investigation was based on a production performed by the Irving, Texas, Community Theatre in March, 1978, directed by the author of this thesis. The paper concerned the problems of producing a play under adverse conditions, such as lack of money, inadequate technical equipment, and a small stage. Chapter I included an investigation of the reviews of the original production in order to establish criteria by which to judge the Irving production. Chapters II and III dealth with varied technical aspects and their application under the adverse conditions. Examples of the technical factors were included in Chapter IV, with a scene synopsis. Chapter V contained a primarily favorable analysis based on the critic's and the audience's judgments, indicating most production elements to be successful.

I dagsläget tenderar många att använda tjänster som hanteras separat. Arbetet undersöker om det är möjligt att sammankoppla ett fåtal tjänster i en gemensam webbapplikation för att underlätta kommunicering mellan tjänsterna samt att förbättra användarvänligheten. Företaget A Great Thing har i åtanke att skapa en webbapplikation som tillåter användare att med hjälp av deras applikation skapa agenter som sköter händelser från användarens begäran, exempelvis “spela upp en låt vid en viss tid”. Metodiken som tillämpats har dels varit en fallstudie och dels användarbaserade metoder i form av enkätundersökning samt ett användartest. Ytterligare undersöktes hur kommunikationen går mellan tjänsters API, och de nödvändiga parametrar som utbyter data. Slutligen evalueras den framtagna prototypen enligt vissa riktlinjer inom användarvänlighet. Examensarbetets resultat är i form av en webbprototyp med fokus på användarvänlighet, implementering av API:er, användartest på faktiska användare samt statistik på efterfrågan av tjänster. Vidare har även en marknadsundersökning utförts för att belysa ekonomiska vinstmöjligheter genom API-distribution. Slutsatsen dras att det är möjligt att sammankoppla API:er och dess tjänster för att uppnå ett användarvänligt gränssnitt samt hur nödvändiga parametrar disponeras på ett effektivt vis. Vidare är förhoppningen att utomstående läsare skapar en förståelse om hur sammankopplingen går till på ett strukturerat och informativt tillvägagångssätt. Även hur olika tekniska metoder inom användarvänlighet kan tillämpas vid konstruktion av prototyper. / Nowadays people tend to use services and appliances that are managed seperately. This thesis examines the possibility of connecting different services into one main web application to faciliate communication between these services. A Great Thing have embraced the need of connecting applications to a single device and therefore, wants to create a web application integrated with the use of agents. These agents are built to manage the events a user request. For example ”Play a song at a specific time”. The methodology applied has partly been a case study and partly user-based methods in form of a survery and a user test. Further research was conducted on communication between service API:s and the necessary parameters that exchange data. Finally, the developed prototype was evaluated according to some usability guidelines. The thesis’s results are presented in the form of a web prototype focused on usability, implementation of APIs, user test of actual users and statistics of demanded services. In addition, a market research has been conducted to highlight economic benefits through API distribution. The conclusion is drawn that it is possible to link API:s and their services to achieve a user-friendly interface and how to use different parameters in an efficient way. Furthermore, the hope is that external readers will understand how the connection between API:s works in a structured and informative approach. Also how different technical methods for usability can be applied in construction of prototypes.

The tremendous increase in usage and complexity of modern communication and network systems connected to the Internet, places demands upon security management to protect organisations¿ sensitive data and resources from malicious intrusion. Malicious attacks by intruders and hackers exploit flaws and weakness points in deployed systems through several sophisticated techniques that cannot be prevented by traditional measures, such as user authentication, access controls and firewalls. Consequently, automated detection and timely response systems are urgently needed to detect abnormal activities by monitoring network traffic and system events. Network Intrusion Detection Systems (NIDS) and Network Intrusion Prevention Systems (NIPS) are technologies that inspect traffic and diagnose system behaviour to provide improved attack protection. The current implementation of intrusion detection systems (commercial and open-source) lacks the scalability to support the massive increase in network speed, the emergence of new protocols and services. Multi-giga networks have become a standard installation posing the NIDS to be susceptible to resource exhaustion attacks. The research focuses on two distinct problems for the NIDS: missing alerts due to packet loss as a result of NIDS performance limitations; and the huge volumes of generated alerts by the NIDS overwhelming the security analyst which makes event observation tedious. A methodology for analysing alerts using a proposed framework for alert correlation has been presented to provide the security operator with a global view of the security perspective. Missed alerts are recovered implicitly using a contextual technique to detect multi-stage attack scenarios. This is based on the assumption that the most serious intrusions consist of relevant steps that temporally ordered. The pre- and post- condition approach is used to identify the logical relations among low level alerts. The alerts are aggregated, verified using vulnerability modelling, and correlated to construct multi-stage attacks. A number of algorithms have been proposed in this research to support the functionality of our framework including: alert correlation, alert aggregation and graph reduction. These algorithms have been implemented in a tool called Multi-stage Attack Recognition System (MARS) consisting of a collection of integrated components. The system has been evaluated using a series of experiments and using different data sets i.e. publicly available datasets and data sets collected using real-life experiments. The results show that our approach can effectively detect multi-stage attacks. The false positive rates are reduced due to implementation of the vulnerability and target host information.

Bidirectional onboard chargers (OBCs) are becoming mainstream commercial charging equipment for electric vehicles (EVs) because of their compactness, flexibility, and demand-response capabilities for power backup. This thesis focuses on the novel phase shift (PS) modulation techniques for efficiency improvement for bidirectional OBCs, including two-stage onboard chargers (TSOBCs) and single-stage onboard chargers (SSOBCs). A comprehensive overview and investigation of the state-of-the-art solutions of bidirectional OBCs are presented. It reviews the current industrial status, industrial applications, and future trends and challenges. A detailed overview of the promising topologies for bidirectional OBCs, including two-stage and single-stage structures, is also discussed in this thesis. Traditional PS modulation has been widely used in the back-end DC/DC converters of the TSOBCs because of its simple implementation. However, it is challenging to keep high efficiency at boundary operating points within wide specifications. Therefore, to improve efficiency at the boundary point for TSOBCs, the hybrid multiple phase shift (HMPS) modulation technique with minimal peak current optimization is presented to maximize the zero-voltage switching (ZVS) range. Compared to traditional single phase shift (SPS) modulation, the experimental results verify that the presented HMPS modulation strategy provides 1%-2% higher efficiency at the boundary points. On the other hand, an improved compact SSOBC topology and novel PS modulation techniques are proposed. Since the traditional PS modulation is challenging for AC/DC converters to keep a unity power factor (PF), novel PS modulation techniques are presented for the proposed SSOBC. Firstly, a sinusoidal single phase shift (SSPS) modulation introduces a sinusoidal phase shift to maintain a high PF and high efficiency within a wide operating point. However, due to the high current at the zero-crossing point of the grid voltage of the SSPS modulation, the novel adaptive sinusoidal single phase shift (ASSPS) modulation is presented to address this issue, which reduces conduction loss and increases efficiency. Secondly, based on the ASSPS modulation, the adaptive sinusoidal extended phase shift (ASEPS) modulation with minimal peak current optimization is presented to introduce one more degree of freedom to extend the ZVS flexibility, which reduces switching loss. Moreover, the minimal peak current optimization reduces transformer current, further decreasing conduction losses. Therefore, the power loss is minimized. Finally, this thesis presents the general design guideline of a 6 kW Silicon Carbide (SiC)-based bidirectional SSOBC, contributing to the further development of bidirectional SSOBC application. Experimental results verify the operating principle and high PF of the proposed SSPS, ASSPS, and ASEPS modulation. 1 kW experimental testing has validated that the peak efficiency is 95.3% with ASSPS modulation and 95.9% with ASEPS modulation. Compared to the existing pulse width modulation (PWM), the ASSPS modulation increased efficiency by 1.1%, and ASEPS modulation further increased by 1.7%. / Thesis / Doctor of Philosophy (PhD)

Railway is a complex system, with many components that are linked with one another. If a failure occurs in a sub-system, it can affect the functionality and the safety of the whole. Signalling represents a crucial component of the railway system because it ensures safety, and it can optimize capacity on the lines. In Europe, private companies control the development and the implementation of new signalling equipment in the railway lines. However, system development processes must satisfy the European standards and the client requirements, which limit the possibility to apply changes in the generic system development process and it leads to employ the same processes in each project, without removing redundant steps and tailoring to the project needs. Recently, Alstom Rail Sweden AB performed the implementation of new signalling system in Älvsjö depot, overcoming several wastes in the process. In this Master Thesis, Älvsjö depot project is compared with a standard project, performed according to the usual procedure used in Alstom projects. The parameters compared are the resource allocation and the days of delay. The results from the data have revealed that projects can benefit through the adoption of the Lean philosophy principles: reduction of waste, increased flexibility, and standardization without eliminating the Stage Gate process in their projects. / Järnvägen är ett komplext system med många komponenter som är kopplade till varandra. Om ett fel uppstår i ett delsystem kan det påverka hela systemets funktionalitet och säkerhet. Signalering utgör en avgörande komponent i järnvägssystemet eftersom den garanterar säkerheten och kan optimera kapaciteten på linjerna. I Europa kontrollerar privata företag utvecklingen och implementeringen av ny signalutrustning på järnvägslinjerna. Systemutvecklingsprocesserna måste dock uppfylla de europeiska standarderna och kundkraven, vilket begränsar möjligheten att tillämpa förändringar i den generiska systemutvecklingsprocessen och leder till att samma processer används i varje projekt, utan att ta bort överflödiga steg och skräddarsy efter projektbehoven. Nyligen genomförde Alstom Rail Sweden AB implementeringen av ett nytt signalsystem i Älvsjö depå och övervann flera slöserier i processen. I detta examensarbete jämförs Älvsjödepåns projekt med ett standardprojekt, utfört enligt det vanliga förfarandet som används i Alstoms projekt. De parametrar som jämförs är resursfördelningen och antalet förseningsdagar. Resultaten från datan har visat att projekt kan dra nytta av att anta Lean-filosofins principer: minskning av slöseri, ökad flexibilitet och standardisering utan att eliminera Stage Gate-processen i sina projekt.

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Quantity Surveyors are considered as the most qualified cost specialists in the construction industry, with their experiences and skills in cost management and control as well as contract management. However, this role is not well recognized in Sweden compared to other countries such as the UK where it’s originated from. And so, the construction industry in Sweden uses other professions for the roles that were supposed to be done by quantity surveyors or cost managers. As a result, the quantity surveyors that have penetrated the Swedish construction industry, face challenges to perform their duties specifically in this case, cost control due to several circumstances. This study has looked into different contractual challenges that face quantity surveyors while performing cost control in building projects. Also, recommendations have been made to help mitigate these challenges and improve cost control in projects. In this master thesis, qualitative study has been performed where quantity surveyors were interviewed regarding cost control and the contractual challenges, they face in building construction projects. The findings were analysed with a theoretical framework and discussed together with previous research and knowledge and in this study principal – agent theory was used. The results of the study showed that poor planning, late involvement of the quantity surveyors in projects, lack of effective communication and poor contract management are the main challenges that face quantity surveyor in performing cost control in building projects. To overcome these challenges, the author suggests that there is a need of increasing awareness on the importance of having quantity surveyors and clearly establish their roles in projects, have proper communication plan, proper contract management and improve skills on quantity surveying software. / Kvantitetbesiktningsman anses vara de mest kvalificerade kostnadsspecialisterna inom byggbranschen, med sina erfarenheter och färdigheter inom kostnadsstyrning och kontroll samt kontrakthantering. Denna roll är dock inte välkänd i Sverige jämfört med andra länder som Storbritannien där den härstammar från. Och så använder byggbranschen i Sverige andra yrken för de roller som skulle göras av kvantitetsmätare eller kostnadsansvariga. Som ett resultat står de kvantitetsmätare som har trängt igenom den svenska byggbranschen inför utmaningar att utföra sina uppgifter specifikt i detta fall, kostnadskontroll på grund av flera omständigheter. Denna studie har undersökt olika avtalsmässiga utmaningar som möter kvantitetsmätare när de utför kostnadskontroll i byggprojekt. Dessutom har rekommendationer gjorts för att mildra dessa utmaningar och förbättra kostnadskontrollen i projekt. I detta examensarbete har en kvalitativ studie utförts där kvantitetbesiktningsman intervjuades angående kostnadskontroll och de kontraktsmässiga utmaningar som de står inför i byggprojekt. Resultaten analyserades med en teoretisk ram och diskuterades tillsammans med tidigare forskning och kunskap och i denna studie användes princip - agentteori. Resultaten av studien visade att dålig planering, sen involvering av kvantitetsmätarna i projekt, brist på effektiv kommunikation och dålig kontrakthantering är de viktigaste utmaningarna för kvantitetsmätaren när det gäller att utföra kostnadskontroll i byggprojekt. För att övervinna dessa utmaningar föreslår författaren att det finns ett behov av att öka medvetenheten om vikten av att ha kvantitetsmätare och tydligt fastställa sina roller i projekt, ha korrekt kommunikationsplan, korrekt kontrakthantering och förbättra färdigheterna i kvantitetsmätningsprogramvara.

I produktutvecklingen förlitar man sig ofta på processer för att driva igenom lyckade projekt, inte minst i företag av större karaktär. En traditionell process som än idag är dominerande i många stora företag är Stage-Gate. Processen är av linjär karaktär och anses vara väldigt effektiv. En uppkommande process med syfte att främja kreativitet är Design Thinking. Processen är iterativ och sätter användaren i fokus. Syftet med detta kandidatexamensarbete är att undersöka hur man i produktutvecklingen hos större etablerade företag kombinerar de två olika processerna Design Thinking och Stage-Gate. Arbetet undersöker kombinationen av en mer iterativ process som Design Thinking och en linjär och mer traditionell Stage-Gate-process och tar reda i vilken mån dessa processer används samt när och varför de används. Arbetet ska också undersöka ifall det finns någon pågående utveckling av processer och i så fall vad en sådan utveckling baseras på. Rapporten grundar sig i en litteraturstudie för att skapa en förståelse om nuvarande kunskapsläge samt undersöka olika synsätt i ämnet. Arbetet bygger också på en empirisk studie av två stora företag i form av semistrukturerade intervjuer. Respondenterna på företagen arbetar aktivt med produktutvecklingsarbete och besitter kunskap om båda processerna Design Thinking och Stage-Gate. Informationen som genererats har sedan tolkats, analyserats samt diskuterats. Slutsatserna som kan dras från undersökningen är att i stora företag används till störst del en Stage-Gatead process då det är viktigt med en tydlig struktur i stora företag. Design Thinking används mest som ett komplement och i situationer då problemet inte är väldefinierat. Utveckling av befintliga processer sker löpande men då handlar det främst om finjustering, att helt byta process är inget som är relevant. / In product development, companies often rely on processes to achieve successful projects, not least in companies of a larger size. A traditional process that is still dominant in many large companies today is Stage-Gate. The process is linear and is considered to be very effective. An emerging process with the goal to encourage creativity is Design Thinking. The process is iterative and puts the user in focus. The purpose of this bachelor's thesis is to investigate how the product development of larger, more established companies combines the two processes Design Thinking and Stage-Gate. The thesis examines the combination of a more iterative process such as Design Thinking and a linear and more traditional Stage-Gate process and analyzes to what extent these processes are used as well as when and why. The report will also investigate if there is any ongoing development of processes and, if so, what such a development is based on. The report is grounded on a literature study to create an understanding of the current state of knowledge and to explore different perspectives within the subject. The thesis is also based on an empirical study of two large companies where semi-structured interviews are used. The respondents at the companies work with product development and have knowledge of both the Design Thinking and Stage-Gate processes. The information generated has then been interpreted, analyzed and discussed. The conclusions that can be drawn from the study are that in large companies a Stage-Gated process is used to a large extent, since it is important to have a clear structure in large companies. Design Thinking is mostly used as a complement and in situations where the problem is not well defined. Development of existing processes is ongoing, but is mainly about fine-tuning, to completely change the process is not relevant.

Québec Université Laval, Bibliothèque 2015