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The orders of linkages that stabilise evolving media worlds are far from obvious. Often undertaken in media ‘laboratories’, the collaborative processes which combine a range of disciplines to develop media worlds are also far from straightforward. Enablers and constraints are as likely to be non-human as they are the people associated with the project. Plugs, wires, switches, protocols and standards - things whose detail can be mind numbingly boring - all have to be worked into effective and stable sets of associations. This thesis describes two knowledge pathways that track through such a project. The first describes the development of a prototype for a website, imagined as a portal for a range of interests around children and media in New Zealand/Aoteoroa. As media worlds are continually being reconfigured and as data circulates across increasingly linked access technologies, many non-government organisations are migrating their work to ‘the web’. ‘The Media Clearinghouse’ project was one of these. Latour’s analytical concept of immutable mobiles provides a way to make sense of some of the work observed whilst his direction to ‘simply follow’ worlds of interest provided the methodological challenge. The second pathway, traces the bibliographic threads of literatures that come from the descriptive genres of Science Technology Studies (STS). Significant amongst these are Leigh Star and Geoffrey Bowker who have elaborated the concept of boundary objects and infrastructures. Star and Griesemer’s seminal description of the Museum of Invertebrate Zoology is compared with a description of an early laboratory by Bruno Latour. These and other writers elaborate on methods that offer ways to render visible the messy, chaotic performances of design and invention. They follow inscriptions - tables, lists, maps, sketches and so on. These things work between the micro and the macro and enable very huge terrains to be assembled in small, ordered spaces. The thesis assembles a list of methods that have some utility for following and describing web design work and perhaps, other information worlds. Having followed and described this writer’s work through the invention of the prototype it is argued that a combinative method has successfully enabled a description that moves in and out of a new information ‘laboratory’.

Opportunistic networks are constructed by devices carried by people and vehicles. The devices use short range radio to communicate. Since the network is mobile and often sparse in terms of node contacts, nodes store messages in their buffers, carrying them, and forwarding them upon node encounters. This form of communication leads to a set of challenging issues that we investigate: congestion, transfer ordering, and resilience. Congestion occurs in opportunistic networks when a node's buffers becomes full. To be able to receive new messages, old messages have to be evicted. We show that buffer eviction strategies based on replication statistics perform better than strategies that evict messages based on the content of the message. We show that transfer ordering has a significant impact on the dissemination of messages during time limited contacts. We find that transfer strategies satisfying global requests yield a higher delivery ratio but a longer delay for the most requested data compared to satisfying the neighboring node's requests. Finally, we assess the resilience of opportunistic networks by simulating different types of attacks. Instead of enumerating all possible attack combinations, which would lead to exhaustive evaluations, we introduce a method that use heuristics to approximate the extreme outcomes an attack can have. The method yields a lower and upper bound for the evaluated metric over the different realizations of the attack. We show that some types of attacks are harder to predict the outcome of and other attacks may vary in the impact of the attack due to the properties of the attack, the forwarding protocol, and the mobility pattern. / WISENET

Boolean Satisfiability (SAT) is a fundamental NP-complete problem of determining whether there exists an assignment of variables which makes a Boolean formula evaluate to True. SAT is a convenient representation for many naturally occurring optimization and decisions problems such as planning and circuit verification. SAT is most commonly solved by a form of backtracking search which systematically explores the space of possible variable assignments. We show that the order in which variable polarities are assigned can have a significant impact on the performance of backtracking algorithms. We present several ways of transforming SAT instances into non-linear objective functions and describe three value-ordering methods based on iterative optimization techniques. We implement and test these heuristics in the widely-recognized MiniSAT framework. The first approach determines polarities by applying Newton's Method to a sparse system of non-linear objective functions whose roots correspond to the satisfying assignments of the propositional formula. The second approach determines polarities by minimizing an objective function corresponding to the number of clauses conflicting with each assignment. The third approach determines preferred polarities by performing stochastic gradient descent on objective functions sampled from a family of continuous potentials. The heuristics are evaluated on a set of standard benchmarks including random, crafted and industrial problems. We compare our results to five existing heuristics, and show that MiniSAT equipped with our heuristics often outperforms state-of-the-art SAT solvers.

ROMCY, Cristina Maria Aleme. Gestão integrada: o município de Icapuí e os programas de administração da orla marítima. 2005. 145 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Pró-Reitoria de Pesquisa e Pós-Graduação, Programa Regional de Pós-Graduação em Desenvolvimento e Meio Ambiente (PRODEMA), Fortaleza-CE, 2005. / Submitted by demia Maia (demiamlm@gmail.com) on 2016-04-29T13:18:31Z No. of bitstreams: 1 2005_ dis_cmaromcy.pdf: 19766007 bytes, checksum: f82be4973f5eb12afb48b2fb1e20bcb9 (MD5) / Approved for entry into archive by demia Maia (demiamlm@gmail.com) on 2016-04-29T13:19:49Z (GMT) No. of bitstreams: 1 2005_ dis_cmaromcy.pdf: 19766007 bytes, checksum: f82be4973f5eb12afb48b2fb1e20bcb9 (MD5) / Made available in DSpace on 2016-04-29T13:19:49Z (GMT). No. of bitstreams: 1 2005_ dis_cmaromcy.pdf: 19766007 bytes, checksum: f82be4973f5eb12afb48b2fb1e20bcb9 (MD5) Previous issue date: 2005 / The disordered occupation of the seashore has been causing usage and environmental degradation conflicts, having as causes the unawareness of the public properties and their environmental resources, as well as the lack of integration between the government sectors and the society. This work aims to contribute to the coastal ordering considering the integration process of the usage and occupation planning policies of the shore, and the sustainable development principles studied through field research, questionnaires, bibliographical surveys, iconographical registrations, and organization and reading of the official cartography of the state and municipality. Based on these elements, the Shore Project promotes the integrated management of the seashore within the union real-estate areas, through its conservation, ordered occupation of their spaces, and usage of the environmental resources through the partnership of the three government levels and the civil society. / A ocupação desordenada da orla marítima tem provocado conflitos de uso e de degradação ambiental tendo como causas o desconhecimento dos bens públicos e dos seus recursos ambientais, como também a falta de integração entre os setores governamentais e a sociedade. Este trabalho contribuiu para o ordenamento costeiro, considerando a complexidade nos processos de integração das políticas de planejamento e de uso e ocupação da orla, tendo como fundamentos básicos metodológicos os princípios do desenvolvimento sustentável. Foram realizados estudos relacionados com uma ampla revisão bibliográfica sobre planejamento e gestão da zona costeira, aliados a pesquisa de campo, aplicação de questionários, registros iconográficos e da organização e leitura cartográfica oficial do estado e município. Com base nestes elementos, apresentou-se uma proposição crítica do Projeto Orla, contribuindo para promover e efetivar a gestão integrada da orla marítima nas áreas do patrimônio da união. Evidenciou-se, como recomendações finais, a necessidade de ampla participação social nas propostas e programas de conservação da paisagem costeira, da ocupação ordenada dos seus espaços e do uso dos recursos ambientais mediante a parceria com os três níveis de governo.

abstract: Recently, the location of the nodes in wireless networks has been modeled as point processes. In this dissertation, various scenarios of wireless communications in large-scale networks modeled as point processes are considered. The first part of the dissertation considers signal reception and detection problems with symmetric alpha stable noise which is from an interfering network modeled as a Poisson point process. For the signal reception problem, the performance of space-time coding (STC) over fading channels with alpha stable noise is studied. We derive pairwise error probability (PEP) of orthogonal STCs. For general STCs, we propose a maximum-likelihood (ML) receiver, and its approximation. The resulting asymptotically optimal receiver (AOR) does not depend on noise parameters and is computationally simple, and close to the ML performance. Then, signal detection in coexisting wireless sensor networks (WSNs) is considered. We define a binary hypothesis testing problem for the signal detection in coexisting WSNs. For the problem, we introduce the ML detector and simpler alternatives. The proposed mixed-fractional lower order moment (FLOM) detector is computationally simple and close to the ML performance. Stochastic orders are binary relations defined on probability. The second part of the dissertation introduces stochastic ordering of interferences in large-scale networks modeled as point processes. Since closed-form results for the interference distributions for such networks are only available in limited cases, it is of interest to compare network interferences using stochastic. In this dissertation, conditions on the fading distribution and path-loss model are given to establish stochastic ordering between interferences. Moreover, Laplace functional (LF) ordering is defined between point processes and applied for comparing interference. Then, the LF orderings of general classes of point processes are introduced. It is also shown that the LF ordering is preserved when independent operations such as marking, thinning, random translation, and superposition are applied. The LF ordering of point processes is a useful tool for comparing spatial deployments of wireless networks and can be used to establish comparisons of several performance metrics such as coverage probability, achievable rate, and resource allocation even when closed form expressions for such metrics are unavailable. / Dissertation/Thesis / Ph.D. Electrical Engineering 2014

Motivation Sequence-based methods for phylogenetic reconstruction from (nucleic acid) sequence data are notoriously plagued by two effects: homoplasies and alignment errors. Large evolutionary distances imply a large number of homoplastic sites. As most protein-coding genes show dramatic variations in substitution rates that are not uncorrelated across the sequence, this often leads to a patchwork pattern of (i) phylogenetically informative and (ii) effectively randomized regions. In highly variable regions, furthermore, alignment errors accumulate resulting in sometimes misleading signals in phylogenetic reconstruction. Results We present here a method that, based on assessing the distribution of character states along a cyclic ordering of the taxa, allows the identification of phylogenetically uninformative homoplastic sites in a multiple sequence alignment. Removal of these sites appears to improve the performance of phylogenetic reconstruction algorithms as measured by various indices of 'tree quality'. In particular, we obtain more stable trees due to the exclusion of phylogenetically incompatible sites that most likely represent strongly randomized characters. Software The computer program noisy implements this approach. It can be employed to improving phylogenetic reconstruction capability with quite a considerable success rate whenever (1) the average bootstrap support obtained from the original alignment is low, and (2) there are sufficiently many taxa in the data set – at least, say, 12 to 15 taxa. The software can be obtained under the GNU Public License from http://www.bioinf.uni-leipzig.de/Software/noisy/.

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