Network lifetime is a key issue in wireless sensor networks where sensor nodes, distributed typically in remote/hostile sensing areas, are powered by finite energy batteries which are not easily replaced/recharged. Depletion of these finite energy batteries can result in a change in network topology or in the end of network life itself. Hence, prolonging the life of wireless sensor networks is important. Energy consumed in wireless sensor nodes can be for the purpose of i) sensing functions, ii) processing/computing functions, and ii) communication functions. For example, energy consumed by the transmit and receive electronics constitute the energy expended for communication functions. Our focus in this thesis is on the efficient use of energy for sensing. In particular, we are concerned with energy efficient algorithms for scheduling the sensing activity of sensor nodes. By scheduling the sensing activity we mean when to activate a sensor node for sensing (active mode) and when to keep it idle (sleep mode). The novel approach we adopt in this thesis to achieve efficient scheduling of sensing activity is an information coverage approach, rather than the widely adopted physical coverage approach. In the physical coverage approach, a point is said to be covered by a sensor node if that point lies within the physical coverage range (or the sensing radius) of that sensor, which is the maximum distance between the sensor and the point up to which the sensor can sense with acceptable accuracy. Information coverage, on the other hand, exploits cooperation among multiple sensors to accurately sense a point even if that point falls outside the physical coverage range of all the sensors. In this thesis, we address the question of how to schedule the activity of various sensor nodes in the network to enhance network lifetime using information coverage. In the first part of the thesis, we are concerned with scheduling of sensor nodes for sensing point targets using information coverage – example of a point-target being temperature or radiation level at a source or point that needs to be monitored. Defining a set of sensor nodes which collectively can sense a point-target accurately as an information cover, we propose an algorithm to obtain Disjoint Set of Information Covers (DSIC) that can sense multiple point-targets in a given sensing area. Being disjoint, the resulting information covers in the proposed algorithm allow a simple round-robin schedule of sensor activation (i.e., activate the covers sequentially). We show that the covers obtained using the proposed DSIC algorithm achieve longer network life compared to the covers obtained using an Exhaustive-Greedy-Equalized Heuristic (EGEH) proposed recently in the literature. We also present a detailed complexity comparison between the DSIC and EGEH algorithms. In the second part of the thesis, we extend the point target sensing problem in the first part to a full area sensing problem, where we are concerned with energy efficient ‘area-monitoring’ using information coverage. We refer to any set of sensors that can collectively sense all points in the entire area-to-monitor as a full area information cover. We first propose a low-complexity heuristic algorithm to obtain full area information covers. Using these covers, we then obtain the optimum schedule for activating the sensing activity of various sensors that maximizes the sensing lifetime. The optimum schedules obtained using the proposed algorithm is shown to achieve significantly longer sensing lifetimes compared to those achieved using physical coverage. Relaxing the full area coverage requirement to a partial area coverage requirement (e.g., 95% of area coverage as adequate instead of 100% area coverage) further enhances the lifetime. The algorithms proposed for the point targets and full area sensing problems in the first two parts are essentially centralized algorithms. Decentralized algorithms are preferred in large networks. Accordingly, in the last part of the thesis, we propose a low-complexity, distributed sensor scheduling algorithm for full area sensing using information coverage. This distributed algorithm is shown to result in significantly longer sensing lifetimes compared to those achieved using physical coverage.

On s'intéresse à une compactification, due à Ekedahl, Lando, Shapiro et Vainshtein, du champ des courbes lisses munies de fonctions méromorphes d'ordres fixés. Celle-ci est obtenue comme une adhérence du champ de départ dans un champ propre. On commence par en donner deux constructions alternatives et on étudie les déformations de ses points. On la relie par la suite à la compactification à la Harris-Mumford par les revêtements admissibles et on donne une interprétation modulaire des points du bord. / We study a compactification, due to Ekedahl, Lando, Shapiro and Vainshtein, of the stack of smooth curves endowed with meromorphic functions having fixed orders. The original compactification is obtained as the closure of the initial stack in a proper substack. We start by giving two alternative constructions of the E.L.S.V compactification and by studying the deformation theory of its points. We finally link it to the Harris-Mumford compactification by admissible covers and give a modular interpretation of boundary points.

This study presents research of role of title photographs in selected czech and foreign daylies. Theoretical part introduces visual culture concepts and role of photographic images in journalism, specificity of photojournalism, photographic genres and title photographs. Next part is dedicated to concept of new values, going from original Galtung / Ruge's taxonomy to contemporary revisited version of Harcup / O'Neill's. The last theoretical chapter introduces concept of gatekeeping and picture editor as visual gatekeeper. The practical part of this study is examining title photographs of 8 czech as well as foreign journals in 4 week long period. I am using method of content analysis, based on paper The content analysis of visual images and Gillian Rose's book Visual analysis. In my study I had applied news values to photographic materials. I chose combination of original Galtung / Ruge's concept together with Harcup / O'Neills contemporary revision, putting attention to entertaining aspects of media contents. The other paramteres I was following in my study were origin, size, topic, theme, negativity, orientation, gender content, etc. As a result I did find that there is very common way how dailyes handle with title photographs, which are having special status among other visual materials. There is...

In this thesis we study two clique-cover problems which have interesting applications regarding the k -bend intersection graph representation: the edge-clique-cover-degree problem and the edge-clique-layered-cover problem. We focus on the complexity of these problems and polynomial time algorithms on restricted classes of graphs. The main results of the thesis are NP-completness of the edge-clique-layered-cover problem and a polynomial-time 2-approximation algorithm on the subclass of diamond-free graphs for the same problem as well as some upper bounds on particular graph classes.

Resumo: A soja (Glycine max L) é a principal oleaginosa cultivada no mundo. Devido a sua intensa utilização proporcionou e proporciona o desenvolvimento de amplo complexo industrial destinado ao seu processamento. Dentre os fatores que influenciam na produção da soja está o preparo de solo, que se realizado de maneira apropriada permite o aumento da produtividade. Entretanto, quando esta prática é realizada de maneira incorreta, é capaz de levar rapidamente a degradação física, química e biológica do solo. O presente trabalho teve como objetivo estudar diferentes sistemas de preparo do solo e coberturas vegetais no comportamento e na demanda energética do cultivar de soja IAC 19. O experimento foi realizado na Fazenda Experimental Lageado, da Faculdade de Ciências Agronômicas da UNESP, Campus de Botucatu. O solo da área experimental foi classificado como NITOSSOLO VERMELHO Distroférrico. O experimento foi constituído por nove tratamentos, sendo a combinação de três sistemas de preparo do solo e três coberturas vegetais. Os sistemas de preparo do solo foram: preparo convencional, preparo reduzido e plantio direto; e as seguintes coberturas vegetais: aveia preta, sorgo e vegetação espontânea. O delineamento experimental foi de blocos ao acaso, em esquema fatorial (3x3), aplicando-se o teste de comparação de médias, Tukey a 5% de probabilidade. De modo geral, a aveia preta apresentou os melhores resultados entre as coberturas vegetais. O sistema de plantio direto foi o tratamento que manteve maior cobertura vegetal na superfície do solo, seguido dos sistemas de preparo reduzido e convencional. O sistema de preparo convencional apresentou o maior consumo horário e operacional de combustível quando comparado com os sistemas de preparo reduzido e de plantio direto. Não foram constatadas diferenças estatísticas significativas entre... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The soybean (Glycine max (L.) Merril) is the main oleaginous plant cultivated in the world and due to its intense usage provided and provides the development of a large industrial complex destined for its processing. The soil handling is among the factors that influence the soy bean production, and if developed appropriately, leads to an increase in productivity. However, when it is carried out wrongly, it can cause the fast physical, chemical and biological degradation of soil. The current work had the objective of studying different systen of soil handling and vegetable covers on the behavior and energetic demand of a soy bean variety. The experiment was carried out on the Experimental Farm Lageado, from Agronomic Science University of UNESP, campus of Botucatu. The experimental soil area had been classified as RED NITOSSOIL Distroférrico. The experiment had been constituted of nine treatments, whit the combination of three systen of soil handling and three vegetable covers. The systen of soil handling had been formed by tillage, reduced handling and no tillage. The vegetable coversused were by black oat, sorghum and spontaneous vegetation. The soybean variety used was IAC19. The experimental designe was in randomized blocks, in a factorial scheme (3x3), and compared by the Tukey Test, with 5% significance level. For the most part, black oat had shown the best results among the vegetable covers. The no tillage systen had been the treatment that maintained the amceumt of vegetable cover on the soil surface, followed by the systen of reduced and tillage handling. The conventional handling system had shown the highest hourly and operational consumption of fuel when compared to the reduced handling method no tillage. Significant statistic differences had not been verified among the treatments for the following parameters: sowing deep, plants height... (Complete abstract, click electronic access below) / Orientador: Carlos Antonio Gamero / Coorientador: Sérgio Hugo Benez / Banca: Silvio José Bicudo / Banca: Ricardo Augusto Dias Kanthack / Mestre

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O presente trabalho tem por objetivo analisar, à luz da semiÃtica greimasiana, a construÃÃo de identidades discursivas dos ex-presidenciÃveis Rousseff e Serra em seis capas das revistas semanais VEJA e Istoà do ano de 2010, publicadas no perÃodo prÃ-eleitoral ou eleitoral. Para tanto, valemo-nos do conceito de identidade discursiva compreendido como âimagem-fimâ, construÃda dialogicamente com base nos simulacros que os textos fornecem, tanto de seu enunciador, quanto de seu enunciatÃrio. (SARAIVA, 2008). Tal conceito corresponde, portanto, a uma identidade advinda e resultante do discurso. Ademais, fazemos uso tambÃm da metodologia de anÃlise de textos verbovisuais conforme sugerida por Floch (2009), Teixeira (2009) e Pietroforte (2012), segundo a qual, num texto sincrÃtico, como o sÃo as capas de revista, devem ser analisadas as figuras e os temas difundidos verbovisualmente no discurso; as categorias topolÃgicas, eidÃticas e cromÃticas do plano de expressÃo plÃstica; a articulaÃÃo entre os dois planos da linguagem; a tensividade presente no texto; a estratÃgia global de comunicaÃÃo. Quanto ao conceito de sincretismo com o qual se trabalha aqui, podemos afirmar que procede de Hjelmslev (2009) e Greimas e CourtÃs (2011). Baseando-nos, por conseguinte, nos linguistas mencionados, consideramos as capas de revistas como textos sincrÃticos porque nelas se manifesta um efeito enunciativo global resultante da articulaÃÃo de mais de uma linguagem no plano da expressÃo. Visto que elas servem como porta de entrada para a manipulaÃÃo do leitor, investigamos como, nesses textos, categorias plÃsticas do plano da expressÃo articulam-se com categorias do plano do conteÃdo para simular as identidades dos candidatos. Nossos resultados mostraram que essa articulaÃÃo cria um jogo de imagens que revela, nas escolhas do enunciador, a euforizaÃÃo ou a disforizaÃÃo da imagem de um candidato em detrimento de outro, pois à produzida, discursivamente, a identidade de competente para um deles e de incompetente para o outro. / This study aims to analyze, according to greimasian semiotics, the construction of discursive identities of the former president candidates Rousseff and Serra on six covers of VEJA and IstoÃ, two Brazilian weekly magazines, which were published in 2010, during the pre-election or election term. We understand discursive identity as âend-imageâ, which is dialogically constructed in texts, based on what is provided about the enunciator and the enunciatee. (SARAIVA, 2008). This concept therefore corresponds to an identity arising and resulting from discourse. Moreover, we also use the methodology of verb-visuals texts analysis as suggested by Floch (2009), Teixeira (2009) and Pietroforte (2012). According to these semioticians, a syncretic text, like magazine covers, should be analyzed through verb-visual figures and themes in the discours; topological, eidetic and chromatic categories of the plastic plane of expression; the relationship between the two planes of language; the tensiveness present in the text; and the global communication strategy. The concept of syncretism comes from Hjelmslev (2009) and Greimas and CourtÃs (2011). From the semiotic point of view of these linguists, the magazine covers are syncretic texts, which have a global enunciative effect as a result of the articulation among the languages on the plane of expression. Seeing that covers are the first device to manipulate readers, it is of interest to examine in these texts how plastic categories of the plane of expression connect with categories of the plane of content in order to simulate the identities of both candidates. Our results show that this articulation creates an image game which can reveal in the enunciatorâs choice whether the candidate is euphoric or dysphorically represented, because it is produced, discursively, the identity of competent to one of the candidates and of incompetent to the other one.

Böcker är, trots ett generellt minskat intresse, fortfarande en viktig del av vårtkulturella samhälle. Att böckers utseende anpassas efter sin målgrupp är ingetovanligt men frågan är om även könet på författaren spelar in gällandeutformningen av omslaget.Syftet med studien var därför att genom en visuell innehållsanalys av böckerspocketomslag kartlägga de skillnader som återfinns på manliga respektivekvinnliga författares omslag.Denna undersökning har baserats på en visuell innehållsanalys där 200pocketomslag analyserades, 100 från svenska författare och 100 från engelskaförfattare. Dessa var därefter jämlikt fördelade mellan könen. I analysenreflekteras det över pocketböckernas motiv, dominerande färg, typsnittsfamiljersamt typsnittsfärger.Resultatet från undersökningen tyder på att kvinnliga författare har ettfemininare utseende på sina böcker överlag, och att svenska kvinnligaförfattares omslag uppvisade flest tecken på en femininare utformning. Det gårdock inte att utesluta att böckernas genre kan ha ett inflytande gällandeböckernas utformning, då det var svårt att precisera genren på många böckeröverlag. / Books are, despite a decline in interest, still an important part of our culturalsociety. It is not unusual for a book’s cover to adapt to its target audience butthe question stands whether the gender of the author functions as a part of thedesign equation as well.The purpose of this study was to through a visual analysis of paperback bookcovers map out differences found between male and female writers’ bookcovers.This study is based on a visual content analysis were 200 paperback coverswere analysed, 100 from Swedish authors and 100 from English authors. Thesewere then evenly divided between the genders. The analysis reflects over themotifs on the covers as well as the dominant colour, font families and fontcolours.The results from the analysis indicate that female authors generally got a morefeminine appearance on their covers, and that covers by Swedish female authorsshowed most signs of a feminine design. Alas, it is impossible to rule out genreas an important influence regarding the books’ cover design. However, as it washard to pinpoint the genre of many of the books analysed it was difficult tomake a distinct connection between genres and books’ cover design.

This thesis is a preliminary investigation into graphic design in 1920s and 1930s Shanghai. I will look at creations of designs on the covers of books and periodicals most closely linked to new literary groups, for that was where a distinctive new idiom of design emerged. I will concentrate on a few figures, including Lu Xun, Tao Yuanqing, Chen Zhifo, and Qian Juntao. Biographical information for each is given, followed by preliminary analysis on some cover designs. Topics covered include artistic characters, the principles of tu'an (a particular understanding of design), and influences from Japan and the West.

A high level of plant mortality on the Bisasar Road landfill, Durban, South Africa initiated an investigation into the primary causes of the mortalities and a search for potentially tolerant plant species. Field studies revealed that volunteer grass growth on cover soils was primarily limited by elevated soil C02, with high soil conductivity and low soil moisture possibly compounding the effect. Cynodon dactylon, the most abundant coloniser of the site appeared to be relatively sensitive to high soil CO2, whilst less common species such as Sporobolis cifricanus and Paspalum Paspoloides appeared to be less sensitive. Further research focused on the high mortality of trees planted on the landfill providing insight into the important variables limiting survival· and the relative differences in performance of 20 tree species. A more rigorous 14-month field experiment was designed and constructed, to assess the performance of 10 of the more promising tree species, the environmental conditions limiting tree growth and the benefit of a deeper layer of better quality topsoil. Some species, such as Barringtonia racemosa, performed relatively well in the field experiment, whilst other species such as Syzygium cordatum, and Harpephyllum caffrom experienced high mortalities and poor growth. The better quality topsoil layer provided little improvement in the performance of the stronger or the weaker species, however significant improvements were recorded for species with relatively intermediate performance. The composition of the soil atmosphere was shown to determine rooting depth. Species that performed better had deeper roots, possibly assisting them in utilising deeper soil moisture reserves. It was concluded that high soil CO2 and low soil O2 levels were the key variables responsible for poor tree survival and growth in this field experiment. A soil fumigation system was designed to provide more control of soil gas concentrations and to experimentally investigate differential species responses and the relative effects of soil CO2 and O2 on tree survival and growth. The apparatus fumigated, for a period of 140 days, the rhizosphere of 80 potted 'tolerant' (Barringtonia racemosa) and 'non tolerant' (Harpephyllum caffrum) trees with 4 treatments consisting of varying combinations of CO2 and 02. The difference in performance of Barringtonia racemosa and Harpephyllum caffrum in the experiment on the landfill was similar to that of the elevated CO2 low O2 fumigation treatment, supporting the premise that landfill gas was the key cause for poor performance of plants. Reduced stomatal conductance and resultant limitations on photosynthesis were found to be indicative of species sensitivity. Low O2 had an additive effect on the impact of elevated CO2 in Harpephyllum caffrum however, even with normal soil O2 levels, 25% soil CO2 had negative growth effects on this sensitive species. Maintenance of plant health and better performance of Barringtonia was attributed to a high inherent level of tissue porosity and aerenchyma. The research provided a greater understanding of the causes of poor vegetation growth and the possible mechanisms of species tolerance to landfill conditions. / Thesis (Ph.D.)-University of Natal, Durban, 2003.

The wide variety of magazines in the South African market and the economic relapse that has been experienc,e d worldwide has given rise to the increasing competition for higher circulation figures and advertising income. This phenomenon especially occurs between publications competing for the same target audience, such as the women's magazines SARIE and rooi rose, competitors over many years in the Afrikaans magazine market. Magazine covers play a critical role in this rivalry due to the direct connection between the popularity of the cover and circulation figures. The more popular the cover of a publication, the higher the sales, circulation and potential profitability will be. Thus it is of the utmost importance for any publication to make the suitable cover selections, considering that the wrong choices can contribute towards a decrease in circulation and eventually fatal consequences for the publication. This study endeavours to determine which requirements magazine covers should meet to be successful and also which tendencies can be identified in the cover choices of SARIE and rooi rose and how these tendencies can be explained. In literature it was found that there are several requirements and directions to which magazine covers should account to be able to be achieving success. It was also found that magazine covers consist of several elements, such as the logo (master-head), cover-girl/-photo, background colours, text and also competitions (announced on the cover). SARIE and rooi rose's covers were analysed in accordance with the requirements for magazine covers. It was found that these magazine covers complied with the formal requirements formulated in the literature consulted. It also appeared that the success of every cover and edition is determined by the cover elements as a whole and not only the popularity of the "cover-girl" only. Several aspects should thus be taken into account when planning the magazine cover. It also appeared that although the cover choice sets an agenda for readers concerning the topics they will eventually be thinking about and discussing, another dimension of agenda-setting rather is to the point, namely the role readers' preferences play (through their personal feedback and buying of magazines) regarding editors' decision in respect of covers. / Thesis (M.A. (Communication Studies))--North-West University, Potchefstroom Campus, 2010