Chunked DASH is getting attention for reducing otherwise high delay oflive segment streaming but there are a lot of unexplored problems associatedwith it. This master’s thesis investigates the difficulties involved withimplementing a chunked DASH player in the browser with JavaScript. A small system containing one JavaScript client and a server which simulateslive streaming by repeating VOD segments is implemented. Issuesrelated to the downloading of chunked segments are addressed and solvedsuch that chunked segments can be streamed within expected delay, andwith accurate throughput metrics. / Chunkad DASH får uppmärksamhet för sin förmåga att minska annars hög fördröjning vid segmentbaserad direktsändning, men det finns många associerade problem som inte har utforskats i någon större utsträckning. Denna masters avhandling undersöker svårigheterna med att implementera en chunkad DASH-spelare i webbläsaren med JavaScript. Ett litet system som innehåller en JavaScript-klient och en server som simulerar direktsändning genom att upprepa VOD-segment implementeras. Frågor relaterade till nedladdning av chunkar behandlas och löses så att innehållet kan sändas inom förväntad fördröjning och med pålitliga mätvärden av genomströmmning.

Au début du 20ème siècle, l'étang de Berre était occupée par de larges prairies sous-marines de Zostera qui ont fortement réduit sous l'impact des pollutions et arrivées massives d'eau douce par le canal EDF. Pollutions et arrivées d'eaux ont beaucoup réduit mais les herbiers ne s'étendent pas vers le large. Cette thèse a donc pour but d'analyser les interactions entre les herbiers sous-marins de l'étang de Berre basé sur l'hypothèse que la dynamique hydro-sédimentaire peut jouer un rôle dans le maintien des herbiers à l'état relique. Dans cette lagune, le vent conditionne l'hydrodynamisme en générant des vagues de vent et des courants.L'atténuation des vagues par l'herbier est en lien avec la hauteur des vagues (dépendant de la vitesse du vent, la longueur de fetch et des effets de réfraction lié à la morphologie de la anse) et est modulée par la biométrie de l'herbier, le niveau d'eau ou la présence de courants. Alors qu'au dessus de l'herbier, les courants sont rapides et fortement influencés par le vent et les vagues de vent, une couche de transition eau-canopée permet la dissipation de l'énergie des vagues et des courants. Dans la canopée, les courants sont très atténués grâce à la présence de l'herbier. L'herbier apparaît comme un élément important de la dynamique sédimentaire car il peut, par sa simple présence, réduire l'hydrodynamisme et modifier l'évolution du fond dans et en arrière de l'herbier et protéger la plage. Le niveau de récurrence de vents forts semble contrôler les évolutions sédimentaires.Les fortes interactions de l'herbier avec la dynamique hydro-sédimentaire laissent penser qu'elle pourrait limiter leur extension dans des zones plus exposées. / Berre lagoon was occupied by extensive meadows at the turn of the 20th century which regressed down under the impact of urban and industrial pollution and inflow of the EDF canal. Even though freshwater inputs and pollutions were drastically reduced respectively in the 1980s and 1990s, meadows have not significantly gained ground. This thesis aims at analysing the interactions between seagrass meadows of Berre lagoon, hydrodynamics and sedimentary processes, based on the postulate that these mechanisms are important in the maintenance of the meadows in their present dispersed form. In the lagoon, winds constitute the dominant influence on hydrodynamics in the lagoon by generating wind waves and currents. Wave attenuation is linked to wave height, which is, in turn, dependent on wind intensity and fetch length and modified by the bay morphology. Wave attenuation is also modulated by meadow biometry, and by water levels and currents.Whereas currents are strong and strongly influenced by wind and wind waves above the meadow, a transition canopy-water layer dissipates waves and currents. In the canopy, currents are thus attenuated.The meadow is not just a passive element in the overall sediment dynamics since it reduces energy and thus modifies substrate changes within and in the back of the meadow, thus protecting the shoreline. However, it is the recurrence of strong wind that seems to drive sedimentary changes. The strong interactions between the meadow and the hydrodynamic and sedimentary processes could limit the extension of the meadow in areas more exposed to waves.

<p>The purpose of this thesis is to construct a"Program Address Generator"(PAG) to a 24-bit Harvard type, RISC DSP processor using the VHDL language. The PAG is a part of the program control unit, and should consist of the following units: </p><p>A system stack for storing jump and loop information. A program counter, a status register, a stack pointer, an operating mode register and two registers called loop address and loop counter register, to support hardware loops. </p><p>The PAG handles the fetch stage of the processor pipeline, and should handle instructions such as the jump, subroutine jump, return from subroutine/interrupt and loop instructions, among others. </p><p>The PAG was successfully designed, and its function verified through extensive tests, where common combinations of ASM instructions were tested. Files for automated testing was created, to support easy testing if only small changes are applied to the PAG.</p>

The purpose of this thesis is to construct a"Program Address Generator"(PAG) to a 24-bit Harvard type, RISC DSP processor using the VHDL language. The PAG is a part of the program control unit, and should consist of the following units: A system stack for storing jump and loop information. A program counter, a status register, a stack pointer, an operating mode register and two registers called loop address and loop counter register, to support hardware loops. The PAG handles the fetch stage of the processor pipeline, and should handle instructions such as the jump, subroutine jump, return from subroutine/interrupt and loop instructions, among others. The PAG was successfully designed, and its function verified through extensive tests, where common combinations of ASM instructions were tested. Files for automated testing was created, to support easy testing if only small changes are applied to the PAG.

Sötvattensmusslor är viktiga i ekosystem där de finns, för människan utgör de även en ekosystemtjänst då de filtrerar vatten. De stora sötvattensmusslorna kallas stormusslor och finns i både sjöar och vattendrag i Sverige. I Vänern har fyra av de inhemska arterna noterats. Fetchen är längden på den öppna vattenytan från en punkt på land till närmsta land eller ö. Beroende på en strands storlek på fetch kan bottensedimentet se annorlunda ut. Musslorna är bottenlevande och spenderar mycket tid nedgrävda i bottensedimenten. När musslorna är uppe och filtrerar på bottenytan sitter de halvt nergrävda med bakänden uppåt. I denna rapport presenteras stormusslornas förekomst och dess relation till stränders fetch. Mer kunskap om stormusslorna behövs för att kunna utveckla ett mer anpassat naturvårdsarbete för dem. Inventering av musslor har skett på 20 olika platser i sydöstra Vänernområdet. Denna studie visar att en trend till ett samband finns mellan förekomst av stormusslor och lokalens fetch. Fetchen påverkar den maximala tätheten som musslorna kan uppnå. Analys ger statistisk signifikans på att tätheten minskar med ökad fetch. Tidigare forskning visar på liknande resultat. Emellertid tycks fler variabler vara beroende faktorer för hur mycket och om fetchen påverkar musslorna. / Freshwater bivalves are important organisms in the ecosystems they live, they also function as an ecosystem service for the human society. Swedish freshwater bivalves are divided into two groups; one with freshwater clams Sphaeriidae, and freshwater mussel with polyphile bivalves that are larger. Freshwater mussel lives in lakes and rivers, in Lake Vänern four species of the Swedish freshwater mussel have been observed. Fetch is the length of the open water from a point on shore to the nearest land or island. The structure of the lake bottom sediment can vary dependent on what value of fetch a shore has. In this report the freshwater mussel’s relation to the shore fetch is presented. More knowledge of the freshwater mussel is needed to develop a more suitable conservation work for them.    Inventory of mussel have been done on 20 different places in the southeast area of Lake Vänern. The results in this study shows a trend towards a relation between presence of freshwater mussel and shore fetch. Analysis on the highest density of mussel when the fetch data is divided in different classes shows a statistic significance for reduced density of mussel with increased fetch. Previous research shows similar results. However, more variables seem to be dependent factors for how and if fetch affect mussel.

The boreal forest in Fennoscandia has been subjected to major loss and fragmentation of natural forests due to intensive forestry. This has resulted in that forest edges are now abundant and important landscape features. Edges have documented effects on the structure, function and biodiversity in forests. Edge influence on biodiversity is complex and depends on interactions between many local and regional factors. This thesis focuses on sharp forest edges and their potential to influence biodiversity at the landscape-level. I have developed a method for quantification and characterization of sharp forest edges by interpretation of colour infrared (CIR) aerial photographs in combination with line intersect sampling (LIS) and sample plots. The method was used to estimate density of forest edge in 28 landscapes (each 1600 ha) in northern Sweden, differing in management intensity, landscape composition and geographical location. Forest edges were described in detail using edge, canopy and neighbourhood attributes. By combining these attributes it was possible to classify edges with respect to levels of exposure. A field experiment was conducted to examine the effect of edge contrast on growth of the old forest lichen Usnea longissima. The edge quantification method is accurate and efficient for estimating the length of sharp forest edges on an area basis (edge density, m ha-1) and for collecting detailed attributes of edges and their surroundings. In northern Sweden, the forest edge density is high (54 m ha-1) but varies extensively (12-102 m ha-1) between landscapes. Edge density is strongly correlated with the level of human disturbance and increases towards the southern part of the study area, at lower altitudes were management intensity is highest. Edge orientation, contrast and neighbourhood size shows an immense variation between edges and also varies between edge types. Regenerating edges are generally of higher contrast and face larger neighbourhoods than natural edges. Maintained edges had high contrast but small neighbourhoods. A larger proportion of edges in mature forests are highly exposed to microclimatic edge influence than edges in general. The field experiment revealed that growth of U. longissima was highest near edges where the vegetation on the adjacent area was sheltering, but not shading, the lichen. In the present thesis, I have provided a valuable tool for estimating density of forest edges with potential to yield information on important factors determining edge influence at landscape-level. The large variability in edge density, edge and neighbourhood attributes imply large differences in microclimate anf thus in the potential for ede influence. Management and conservation strategies must incorporate these factors to realistically address edge influence on biota at the landscape-level.

En vue de comprendre et prévoir les modes de dispersion des polluants émis dans les zones urbanisées, des simulations numériques sont menées à haute résolution. L'objectif est de reproduire les caractéristiques atmosphériques au-dessus d'un milieu complexe urbanisé. On a développé une méthode précise de mise en œuvre des simulations numériques de l'atmosphère urbaine à haute résolution spatiale en se basant sur trois outils complémentaires, optimisés sur l'exemple de Marseille : le modèle atmosphérique SUBMESO, en mode SGE (simulation des grandes échelles), le modèle de sol pour les échelles sub-meso urbanisé SM2-U, le logiciel de cartographie des caractéristiques morphologiques de la canopée urbaine DFMap. Pour pouvoir simuler l'atmosphère de villes côtières, on a développé et validé une méthode de calcul des flux à l'interface mer – atmosphère adaptée aux données de température disponibles par mesure ou télédétection. Une étude de sensibilité est ensuite menée sur une configuration académique de ville dans son environnement rural et/ou côtier, à l'aide de douze simulations permettant d'évaluer les rétroactions entre le modèle de sol et le modèle atmosphérique. Cinq autres simulations sont effectuées sur la région marseillaise au cours d'une période d'observation intensive de la campagne expérimentale CLU – ESCOMPTE, avec trois grilles emboîtées, permettant la première validation du couple SUBMESO – SM2-U, l'analyse des interactions entre la ville, les systèmes de brise et la topographie, et aussi l'étude des champs turbulents à très haute résolution. La méthode développée peut être utilisée pour l'étude de la qualité de l'air d'autres agglomérations.

Made available in DSpace on 2017-07-10T18:13:28Z (GMT). No. of bitstreams: 1 Thamis Meurer.pdf: 1244068 bytes, checksum: 7fedbdd5b53b39bf3ab6cb34f4fac17a (MD5) Previous issue date: 2011-04-28 / The family Characeae, represented in Brazil by the genera Chara and Nitella, is considered the closest living relatives of terrestrial plants and play several ecological roles, such as the increase of water transparency and habitat complexity. This research aimed to verify the composition and structure of Characeae community at Itaipu reservoir (24°05´S e 25°33´S; 54°00´W e 54°37´W), formed in Parana river, relating them to simple environmental variables, such as conductivity, water transparency and fetch. Samples were collected in eight arms of rivers that form the Brazilian side of the reservoir (Arroio Guaçu, São Francisco Verdadeiro, São Francisco Falso, São Vicente, São João, Ocoí, Pinto e Passo Cuê). A total of 17 taxa were identified, of which Chara hydropitys Reichenbach, C. rusbyana Howe, Nitella axillaris A. Braun, N. glaziovii G. Zeller, N. gracilis (Smith) C. Agardh, N. hyalina (DC) C. Agardh, N. inversa Imahori and N. microcarpa Braun, represent new citations in the Itaipu Reservoir and Paraná State. Chara guairensis, Nitella furcata and Nitella glaziovii showed the largest geographical ranges, while Chara hidropytis and Chara rusbyana showed more restricted distribution. Furthermore, it was found that among the environmental factors considered important for the establishing of charophytes at the tributaries of the reservoir, the underwater radiation positively affects the occurrence of the genera Chara and Nitella, while fetch values showed negative influence on the occurrence of genus Nitella during the period analyzed. / A família Characeae, representada no Brasil pelos gêneros Chara e Nitella, é considerada a ancestral mais próxima das plantas terrestres e possui uma série de papéis ecológicos, entre eles o aumento da transparência da água, aumento da complexidade de habitat. O presente trabalho objetivou verificar a composição e estrutura da comunidade de Characeae no reservatório de Itaipu (24°05´S e 25°33´S; 54°00´W e 54°37´W), formado no rio Paraná, relacionando-as com variáveis ambientais simples, tais como: condutividade, transparência da água e fetch. As coletas foram realizadas em oito braços de rios que formam a margem brasileira do reservatório (Arroio Guaçu, São Francisco Verdadeiro, São Francisco Falso, São Vicente, São João, Ocoí, Pinto e Passo Cuê). Foram identificados 17 táxons, dos quais Chara hydropitys Reichenbach, C. rusbyana Howe, Nitella axillaris A. Braun, N. glaziovii G. Zeller, N. gracilis (Smith) C. Agardh, N. hyalina (DC) C. Agardh, N. inversa Imahori e N. microcarpa Braun, todas novas citações no reservatório de Itaipu e Estado do Paraná. Chara guairensis, Nitella furcata e Nitella glaziovii apresentaram as maiores abrangências geográficas, enquanto Chara hidropytis e Chara rusbyana apresentaram distribuição mais restrita. Além disso, verificou-se que entre os fatores ambientais considerados importantes para o estabelecimento dos carófitos nos afluentes do reservatório, foi encontrado que a radiação subaquática afeta positivamente a ocorrência dos gêneros Chara e Nitella, enquanto valores de fetch demonstraram influência negativa sobre a ocorrência do gênero Nitella durante o período analisado.