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Open Source Intelligence using social media is a practice which gives military intelligence analysts a window into the thoughts and minds of an online population. Using Social Network Analysis, user interactions on Twitter will be modeled as a weighted and directed network. Topic modeling through Latent Dirichlet Allocation uncovers the topics of discussion in Tweets and is then integrated into a multi-layer network which allows users to be connected to the conversations with which they have participated. Influential users in this network as well as highly connected groups of individuals are then discovered to paint a picture for intelligence analysts of the online landscape with which they are dealing. The results of this research demonstrate that the inclusion of topics in the social network allows for more robust findings in influential users when analysts collect Tweets from a variety of discussions through the use of more general search queries. PageRank was identified as the best performing influence ranking method for this problem context and two potential community identification methods were analyzed.

We increasingly depend on well-behaved networks in the course of every-day activities for business, community, government, science, and recreation. And with more people demanding a greater variety of services comes sharp disagreement about which needs are most important. Unfortunately, today's technology is inadequate to guarantee the performance of dynamic and diverse workloads in such a way that we are prevented from hurting each other's goals.No one likes waiting in traffic, whether on a road or on a computer network. Stuttering progress and slow interactive feedback annoy everyone and cost time and money. A network should aim to (1) minimize latency, (2) maximize bandwidth, (3) share resources according to agreements, (4) enable incremental deployment, and (5) minimize administrative overhead. Many technologies have been developed, but none yet satisfactorily address all five of these goals. The best performing solutions to date achieve some success in goals 1-3, but they often downplay the importance of goals 4-5. Solutions almost always require coordinated configurations across many pieces of a network, but they end up being either impractical or suffer poor performance when even a single piece of a network is not cooperating.In this dissertation I present an overview of the multilayered problem surrounding network performance, a transport-level solution called TCP Inigo, and foundations for a clean-slate queueing discipline solution based on a new combination of recent real-time and economic scheduling algorithms. TCP Inigo uses independent delay-based algorithms on the sender and receiver. In emulated experiments with single administrative domains, a situation common in data centers or a single HPC cluster, TCP Inigo's fairness, bandwidth, and latency indices are up to 1.3× better than the best available solution. When deployed in a more complex environment, such as across administrative domains, TCP Inigo performs up to 42× better.

Recent research on measuring world city network formation has shown a mixture of hierarchical and regional tendencies. Using specially created data, the relative importance of these tendencies, and different regional sets of world cities, are evaluated using a discriminant analysis research model. It is found that regionality is at least as important as hierarchy amongst world cities. This contradicts the world city literature where the concept of a "world city hierarchy" dominates and regional patterning of world cities is relatively neglected. As well as suggesting a reorientation in world cities research, these findings have wider implications for globalisation in general. The latter is not, and I argue cannot, produce a homogeneous global space, which is what a single global hierarchy implies. Rather, it is always the case that globalisation processes simultaneously create more than one large scale of social activity. (Original abstract)

Why are the poor susceptible to clientelism, and what factors shield them from the influence of vote buying? We explore the role of both formal and informal social networks in shaping the likelihood of being targeted with private inducements. We argue that when the poor lack access to formal social networks, they become increasingly reliant on vote buying channelled through informal networks. To test our theory, we build the informal, family-based network linkages between voters and local politicians spanning a city in the Philippines. We then collect survey data on formal network connections, electoral handouts, and voting behaviour of 900 voters randomly drawn from these family networks. We show first that campaigns disproportionately target poorer voters. We then show that familial ties further influence targeting among poor voters. Finally, we show that access to formal networks such as workers' associations mitigate voter fears of punishment for failing to reciprocate.

Underwater Acoustic Sensor Networks (UASNs) have attracted increasing interest in recent years due to their extensive commercial and military applications. However, the harsh underwater channel causes many challenges for the design of reliable underwater data transport protocol. In this paper, we propose an energy efficient data transport protocol based on network coding and hybrid automatic repeat request (NCHARQ) to ensure reliability, efficiency and availability in UASNs. Moreover, an adaptive window length estimation algorithm is designed to optimize the throughput and energy consumption tradeoff. The algorithm can adaptively change the code rate and can be insensitive to the environment change. Extensive simulations and analysis show that NCHARQ significantly reduces energy consumption with short end-to-end delay.

The social context of political decision making is a critical component of explanations of political behavior. Little research, however, has focused on direct observation of the social circles that transmit political information & influence. The influences of local, neighborhood-based social networks on individual political attitudes are described on the basis of interview data from about 250 Rs to a 1979 pilot study for the 1980 National Election Survey conducted by the Center for Political Studies. A model of the sources & impacts of interpersonal networks in the mass public is proposed. 2 Tables, 1 Appendix, 77 References. Modified HA.

1. Activity spaces, biographies, social networks and their welfare gains and externalities : some hypotheses and empirical results / Kay W. Axhausen -- 2. Qualitative interviews on the formation and maintenance of social networks as foundation for quantitative survey instruments / Timo Ohnmacht -- 3. Egocentric networks in Zurich : quantitative survey development, data collection and analysis / Andreas Frei and Timo Ohnmacht -- 4. Personal networks in a population-wide network structure / Matthias Kowald -- 5. Country specific characteristics matter / Andreas Frei. [et al.] -- 6. Personal characteristics, social contacts and transport systems / Juan A. Carrasco -- 7. Dynamic social networks and travel / Fariya Sharmeen, Theo Arentze and Harry J.P. Timmermans.

AbstractSegregation has been one of the most persistent features of urban life and, accordingly, one of the main subjects of enquiry in urban studies. Stemming from a tradition that can be traced back to the Chicago School in the early twentieth century, social segregation has been seen as the natural consequence of the social division of space. Such naturalized understanding of segregation as 'territorial segregation' takes space as a surrogate for social distance. We propose a shift in the focus from the static segregation of places—where social distance is assumed rather than fully explained—to how social segregation is reproduced through embodied urban trajectories. We aim to accomplish this by exploring the spatial behaviour of different social groups as networks of movement that constitute opportunities for co‐presence. This alternative view recasts the original idea of segregation as 'restrictions on interaction' by concentrating on the spatiality of segregation potentially active in the circumstances of social contact and encounters in the city. This approach to segregation as a subtle process that operates ultimately through trajectories of the body is illustrated by an empirical study in a Brazilian city.

Wireless Ad Hoc Networks comprise a fast developing research area with a vast spectrum of applications. Wireless sensor network systems enable the reliable monitoring of a variety of environments for both civil and military applications. The Energy efficiency continues to be a key factor in limiting the deployability of ad-hoc networks. Deploying an energy efficient system exploiting the maximum lifetime of the network has remained a great challenge since years. The time period from the instant at which the network starts functioning to the time instant at which the first network node runs out of energy, i.e. the network lifetime is largely dependent on the system energy efficiency. In this paper, we look at energy efficient protocols, which can have significant impact on the lifetime of these networks. The cluster heads get drain out maximum energy in the wireless ad hoc networks. We propose an algorithm that deals with minimizing the rate of dissipation of energy of cluster heads. The algorithm LEAD deals with energy efficient round scheduling of cluster head allocation of nodes and then followed by allocation of nodes to the cluster heads maximizing network lifetime using ANDA [1, 2]. We compare our results with the previous works.

This book focuses on recent technical advancements and state-of-the art technologies for analyzing characteristic features and probabilistic modelling of complex social networks and decentralized online network architectures. Such research results in applications related to surveillance and privacy, fraud analysis, cyber forensics, propaganda campaigns, as well as for online social networks such as Facebook. The text illustrates the benefits of using advanced social network analysis methods through application case studies based on practical test results from synthetic and real-world data. This book will appeal to researchers and students working in these areas.

This paper applies practice theory to assess the evolution of American foreign policy. It does so by examining the daily schedules of President Truman. Data has been collected from the Truman Presidential Library's daily appointments calendar. The author has reviewed the daily presidential appointments of President Truman from April 12th, 1945, the day in which President Truman assumed the role of President, to January 20th, 1953, President Truman's final day in office. The assumption derived from practice theory is that the President will be more willing to talk to dignitaries from states they have strong relationships with, and thus the quantity of interactions will be indicative of an administration's relationships with other states. This paper uses social network analysis to assess whether the theoretical assumptions of practice theory can effectively capture the expansion of American diplomatic relations in the post-war period described by G John Ikenberry in Liberal Leviathan and Liberal Order and Imperial Ambition. Discipline: Political Science Honours Faculty Mentor: Dr. Jean-Christophe Boucher