Altmetrics is a new bibliometric subfield that uses data from online platforms and social and mainstream media to track attention to and impact of scholarly content. Qualitative research is needed to increase knowledge of altmetrics and of what they may indicate about scholarly publications’ impact and influence. Through analyzing the second-largest source of altmetric events, tweets to academic articles, this thesis extends our understanding of these metrics. Using content analysis and an adapted framework for categorizing acts by levels of engagement, I analyzed 1,200 tweets to four humanities articles, recording their engagement with the articles, sentiment, hashtag use, and @mentions. I also categorized 203 of the tweeting accounts. There is considerable inter-article variation among tweets to the four articles. Overall, however, the tweets evidence low engagement with the articles, the retweet percentage is high, and many of the tweets are traced to few accounts. Contradicting prior suggestions that tweets may be particularly suited to indicating public engagement with scholarly articles, a large proportion of the tweets appear to be from academics. Confirming findings of prior studies, the results indicate that academics use Twitter to filter scholarly literature. I conclude that a single altmetric score is too reductive and of negligible use without deeper qualitative analysis. Unlike some altmetrics indicators that may reveal impact, tweets to articles rather indicate attention, casting doubt on the claim that altmetrics as a whole measure impact. Despite these limitations, tweets to articles and altmetrics more broadly can provide meaningful information not conveyed by citations.

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The movement of the exotic and destructive plant pathogen Phytophthora ramorum into unquarantined areas via the plant nursery trade provides a potential outlet for transmission into eastern United States forests. A two-year survey of Phytophthora species in a forest adjacent to an ornamental plant nursery in Mississippi isolated P. ramorum 20 times from water and once from vegetation, with an additional detection of 14 Phytophthora species and one provisional species. Isolates were recovered from soil, water, and vegetation using baiting and filtering techniques, and verified by their DNA through Polymerase Chain Reaction (PCR) followed by genomic sequencing. This study confirms the ability of P. ramorum to sustain itself in Mississippi, although disease progression appears to be inhibited by the relatively small window of favorable environmental conditions.

Critical infrastructures like oil & gas, power grids, water treatment facilities, domain name system (DNS) etc., are attractive targets for attackers — both due to the potential impact of attacks on such systems, and due to the enormous attack surface exposed by such systems. Unwarranted functionality in the form of accidental bugs or maliciously inserted hidden functionality in any component of a system could potentially be exploited by attackers to launch attacks on the system. As it is far from practical to root out undesired functionality in every component of a complex system, it is essential to develop security measures for protecting CI systems that rely only on the integrity of a small number of carefully constructed components, identified as the trusted computing base (TCB) for the system. The broad aim of this dissertation is to characterize elements of the TCB for critical infrastructure systems, and outline strategies to leverage the TCB to secure CI systems. A unified provider-middleman-consumer (PMC) view of systems was adopted to characterize systems as being constituted by providers of data, untrusted middlemen, and consumers of data. As the goal of proposed approach is to eliminate the need to trust most components of a system to be secured, most components of the system are considered to fall under the category of “untrusted middlemen.” From this perspective, the TCB for the system is a minimal set of trusted functionality required to verify that the tasks performed by the middle-men will not result in violation of the desired assurances. Specific systems that were investigated in this dissertation work to characterize the minimal TCB included the domain name system (DNS), dynamic DNS, and Supervisory Control and Data Acquisition (SCADA) systems that monitor/control various CI systems. For such systems, this dissertation provides a comprehensive functional specification of the TCB, and outlines security protocols that leverage the trust in TCB functionality to realize the desired assurances regarding the system.

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Nowadays, scholars are encouraged to use video for research dissemination. In most of the EU and national research projects, it is the hard requirement that the project results need to be disseminated to the public in multiple channels, e.g. video, webpage, etc. Thus the general aim of this master thesis research has arisen from this challenge faced by scholars, who normally have limited experience in the media production workflow and collaborating with video producers. To bridge the gap between researchers and media experts, better workflow guidance on production management is needed. In this study, the literature on three conventional video production management methods is reviewed and compared, aiming to identify the advantage and disadvantage of the methods for the research project video production. Emerging from the key findings, a novel management model is developed to meet the needs of researchers. Meanwhile, a logic workflow is proposed accordingly. The proposed approach is implemented and evaluated with a case study on a real video production project for a research centre at KTH. The limitation of the study is discussed in the end, with the suggestion given on further research. / Idag uppmanas forskare att använda video för forskningsförmedling. I de flesta EU-och nationella forskningsprojekt är det ett hårt krav att projektresultaten måste sprida sig till allmänheten via flera kanaler, t.ex. video, webbsida etc. Således har den generella målsättningen med detta examensarbete uppstått på grund av denna utmaning som forskare står inför, som normalt sett har begränsad erfarenhet av medieproduktionsarbete och av samarbete med videoproducenter. För att överbrygga klyftan mellan forskare och medieexperter behövs bättre arbetsflödesledning för produktionsledning. I denna studie granskas litteraturen för tre konventionella videoproduktionshanteringsmetoder och jämförs för att identifiera fördelar och nackdelar med metoderna för ett forskningsprojekts videoproduktion. En ny ledningsmodell har utvecklats för att möta forskarnas behov. Under tiden föreslås ett logiskt arbetsflöde. Det föreslagna tillvägagångssättet genomförs och utvärderas med en fallstudie gällande ett verkligt videoproduktionsprojekt för ett forskningscenter vid KTH. Begränsningen av studien diskuteras i slutet, med förslag på vidare forskning.

Peer-to-peer swarming, as used by BitTorrent, is one of the de facto solutions for content dissemination in today’s Internet. By leveraging resources provided by users, peer-to-peer swarming is a simple, scalable and efficient mechanism for content distribution. Although peer-to-peer swarming has been widely studied for a decade, prior work has focused on the dissemination of one commodity (a single file). This thesis focuses on the multi-commodity case. We have discovered through measurements that a vast number of publishers currently disseminate multiple files in a single swarm (bundle). The first contribution of this thesis is a model for content availability. We use the model to show that, when publishers are intermittent, bundling K files increases content availability exponentially as function of K. When there is a stable publisher, we consider content availability among peers (excluding the publisher). Our second contribution is the estimate of the dependency of peers on the stable publisher, which is useful for provisioning purposes as well as in deciding how to bundle. To this goal, we propose a new metric, swarm self-sustainability, and present a model that yields swarm self-sustainability as a function of the file size, popularity and service capacity of peers. Then, we investigate reciprocity and the use of barter that occurs among peers. As our third contribution, we prove that the loss of efficiency due to the download of unrequested content to enforce direct reciprocity, as opposed to indirect reciprocity, is at most two in a class of networks without relays. Finally, we study algorithmic and economic problems faced by enterprises who leverage swarming systems and who control prices and bundling strategies. As our fourth contribution, we present two formulations of the optimal bundling problem, and prove that one is NP hard whereas the other is solvable by a greedy strategy. From an economic standpoint, we present conditions for the existence and uniqueness of an equilibrium between publishers and peers.

Shanghai is one of has been a city of high economic and social importance since the early 20th century. The form and historical background of cultural heritages in its downtown districts is different to those in other Chinese cities with protected historical areas such as for instance the Bund area. The text identifies the uniqueness of heritage management regulations in Shanghai, and put forward questions about the function of documentary heritage in urban development with a case study about the newly updated Shanghai Jewish Refugees Memorial Museum. The general urban development of Shanghai is reviewed in the context of the incorporation of heritage in urban planning and specifically the development plans for the Bund area where the museum is located. The history of the Jewish community in Shanghai and of the museum itself is analysed based on the museum exhibition and layout, as also the experience of museum visitors. The thesis builds on archive studies, peer interviews and survey investigation. 292 survey answers have been collected from visitors on the experience of the museum. The results of the survey together with the interviews, individual experience and policy studies, are drawn upon to discuss the role of the museum in urban planning and how it can be developed. It is stressed that the documentary heritage is helpful in minimizing conflict between the everyday experience of heritage and amore exclusive academically informed view on heritage. It is also recommended that multidirectional support will be constructed between document collection, historically reserved areas and the central business district in Shanghai.

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