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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Interações ecológicas associadas a Ipomoea carnea subs. fistulosa (Martius e Choise) (convolvulaceae) em uma área de caatinga no Nordeste do Brasil

MARTINS, Joanny Kelly Silva dos Santos 21 July 2015 (has links)
Submitted by (ana.araujo@ufrpe.br) on 2016-08-23T12:05:53Z No. of bitstreams: 1 Joanny Kelly Silva dos Santos Martins.pdf: 1467107 bytes, checksum: 51dc871b39b7f000a36a8445217f21da (MD5) / Made available in DSpace on 2016-08-23T12:05:54Z (GMT). No. of bitstreams: 1 Joanny Kelly Silva dos Santos Martins.pdf: 1467107 bytes, checksum: 51dc871b39b7f000a36a8445217f21da (MD5) Previous issue date: 2015-07-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The objective of this study was to survey the richness and abundance of pollinators, herbivores, ants and other predators associated to Ipomoea carnea subs. fistulosa, addition to assessing the indirect effects of florivory and the influence of patrolling ants associated with extrafloral nectaries on pollinators. The study was conducted durig eight months (August/2014 – March/2015) at the Fazenda Tamanduá, municipality of Santa Terezinha, Paraíba state, Brazil. It was quantified the number of pollinator visits in flowers with and without patrolling ants and flowers with simulated florivory. The number of herbivores per inflorescence and the occurrence of florivory were recorded in an experiment conducted from 5 am to 5 pm. Arthropods were collected monthly to record the richness and abundance. The temporal variation of florivory and production of buds, flowers and fruits were recorded monthly. The results of the effect of the damage and the presence of floral ants showed that both cause a decrease in the total number of visits. This can be explained by the fact that the floral damage was the loss of important floral attributes. Additionally, bees can evaluate the pattern of flower symmetry distance and detect predators corroborating the hypothesis that predators such as ants, remove pollinators of plant-pollinator systems. These effects may be considered risky for Ipomoea carnea subs. fistulosa, since it is a self-incompatible species and depends on the activity of pollinators for its fertilization. The composition of the arthropod fauna associated with plant species under study was represented by five groups: Araneae, Coleoptera, Hymenoptera, Diptera and Hemiptera. The highest abundance of herbivores occurred in months with low rainfall. The florivory rates were high, and more severe in the dry season. The number of ants associated to extrafloral nectaries increased directly with the abundance of herbivores over months. The multitrophic system studied showed complex, featuring a high richness of associated arthropods and various guilds among the trophic levels. During the dry season in the caatinga, Ipomoea carnea subs. fistulosa is one of the few species that persist with leaves and flowers, this enables the populations of I. carnea constitute major indicator spots resources for present herbivores. This may have been one of the main causes for the abundance of herbivores and floral herbivory rate was higher in the months with less precipitation. Overall the data suggest that abundance of herbivores was related to the quality and availability of plant resources, reflecting on other trophic levels as in a bottom-up model of trophic cascade. / O objetivo deste trabalho foi realizar um levantamento da riqueza e abundância dos polinizadores, herbívoros, formigas e predadores de insetos associados a Ipomoea carnea subs. fistulosa, bem como avaliar os efeitos indiretos da florivoria e a influência do patrulhamento de formigas associadas aos nectários extraflorais sobre os polinizadores. Este trabalho foi realizado em oito meses de coleta (agosto de 2014 a março de 2015) na Fazenda Tamanduá, no município de Santa Terezinha, PB. Foi quantificado o numero de visitas de polinizadores em flores com e sem patrulhamento de formigas e em flores com florivoria simulada. O número de herbívoros por inflorescência e a ocorrência de florivoria foi registrado em um experimento realizado das 5h às 17h. Os artrópodes foram coletados mensalmente para registro da riqueza e abundância. E a variação temporal da florivoria e produção de botões, flores e frutos foi registrada mensalmente. Os resultados do efeito do dano floral e presença de formigas mostraram que ambos provocam decréscimo no número de visitas totais. Isso pode ser justificado pelo fato de que o dano floral consistiu na perda de atributos florais importantes. Adicionalmente abelhas podem avaliar o padrão de simetria da flor à distância e detectar predadores corroborando com a hipótese de que predadores, tal como formigas, retiram polinizadores dos sistemas planta-polinizador. Estes efeitos para Ipomoea carnea subs. fistulosa podem ser considerados de risco, uma vez que é um espécie autoincompatível e depende da atividade dos polinizadores para que a sua fecundação ocorra. A composição da fauna de artrópodes associados a espécie vegetal em estudo foi representada por cinco grupos: Araneae, Coleoptera, Hymenoptera, Diptera e Hemiptera. O sistema multitrófico estudado se mostrou complexo, apresentando uma grande riqueza de artrópodes associados e variadas guildas dentre os níveis tróficos. Durante a estação seca na caatinga Ipomoea carnea subs. fistulosa, é uma das poucas espécies que persistem com folhas e flores, fato que faz com que as populações de I. carnea constituam grandes manchas indicadoras de recursos para os herbívoros presentes. Esta pode ter sido uma das principais causas para que a abundância de herbívoros e taxa de herbivoria floral tenha sido mais alta nos meses com menor precipitação. De maneira geral os dados sugerem que abundância de herbívoros respondeu a qualidade e disponibilidade dos recursos vegetais, refletindo nos demais níveis tróficos como em um modelo bottom-up de cascata trófica.
12

Lokala planeringsutmaningar för statligt megaprojekt : En studie av mindre kommuners förberedande av höghastighetsjärnvägen Ostlänken

Hörnedal, Adam January 2016 (has links)
Studien syftar till att analysera processer och relationer i den nätverksstruktur som innefattar både lokala, regionala och statliga aktörer i megaprojektet Ostlänken, med tonvikt på de små kommunerna Nyköping och Trosa. Uppsatsens teoretiska förhållningssätt härrör från forskning inom nätverksstyrning (governance) och megaprojekt. Dessa forskningsteman används i den valda metodansatsen för att vidare kunna beskriva och tolka nätverksstyrning för ett megaprojekt i den lilla kontexten. Forskningsstudien utgör således en kvalitativ sådan, där insamling av primärbaserad data sker genom intervjuer med olika beslutsfattare på nationell, regional och lokal styrningsnivå. Studiens resultat visar hur de mindre kommunerna kompenserar för ett maktunderskott genom att dels tillsammans med andra lokala och regionala aktörer samverka i nätverk, dels genom att komma med ett väl genomarbetat underlag för planering av Ostlänken till staten. Relationerna inom Ostlänkens nätverksstruktur påvisar att det råder en storstadsnorm på statlig nivå. Denna norm återges av att staten låter sig uppföra krav på bland annat befolkningsmängd, för de kommuner som eftersträvar en stationslokalisering, samt att en uttalad ändpunktstrafik bör råda mellan de tre storstadsregionerna Stockholm-Göteborg-Malmö. En ytterligare konklusion är hur det anses behöva lokala och regionala påverkansnätverk för att ett projekt av en sådan dignitet ska kunna förverkligas, vilket belyser statens tillbakadragna roll och en planeringsprocess karaktäriserad av bottom-up.
13

Binding of visual features in human perception and memory

Jaswal, Snehlata January 2010 (has links)
The leit motif of this thesis is that binding of visual features is a process that begins with input of stimulation and ends with the emergence of an object in working memory so that it can be further manipulated for higher cognitive processes. The primary focus was on the binding process from 0 to 2500 ms, with stimuli defined by location, colour, and shape. The initial experiments explored the relative role of topdown and bottom-up factors. Task relevance was compared by asking participants to detect swaps in bindings of two features whilst the third was either unchanged, or made irrelevant by randomization from study to test, in a change detection task. The experiments also studied the differences among the three defining features across experiments where each feature was randomized, whilst the binding between the other two was tested. Results showed that though features were processed to different time scales, they were treated in the same way by Visual Working Memory processes. Relevant features were consolidated and irrelevant features were inhibited. Later experiments confirmed that consolidation was aided by iconic memory and the inhibitory process was primarily a post-perceptual active inhibition.
14

Radical change in energy intensive UK industry

Griffin, Paul January 2015 (has links)
Managing energy demand is essential to energy security and climate change mitigation. The industrial sector accounts for over a fifth of UK primary energy demand and greenhouse gas emissions. Energy intensive industry is uniquely restricted in the way it uses energy and emits greenhouse gasses. In this thesis, the potential of radical measures to achieve significant energy demand reduction and emissions abatement in UK energy intensive industry is assessed. Adopted is a multidisciplinary approach combining thermodynamic and techno-economic analysis techniques. Bottom-up assessments are applied to key energy intensive sectors of industry to capture the diverse and interactive array of technological characteristics invisible from a top-down perspective. Detailed projection models are built to design and analyse technology roadmaps for the sectors out to 2050. In an illustrative roadmap assessment, the technological pathways of radical process transition and carbon sequestration were each shown to achieve about 80% abatement in 2050 from 1990 emissions levels. Radical process transition achieved greater abatement before 2030 and this was reflected in lower cumulative emissions over the full period. Higher risk is associated with carbon sequestration from its reliance on timely access to CO2 transport and storage technology to compensate for lower short-medium term abatement. Although, combining carbon sequestration with high levels of biomass combustion indicated the largest potential abatement to 2050. Abatement economics in the iron and steel sector are notably sensitive to resource costs and the carbon trading price. The carbon trading price influences relative production costs in favour of higher abating pathways, but increases absolute costs. This signals the need for supportive policy measures that accelerate technology development and deployment while mitigating the risk of the carbon trading price to competitiveness. Some carbon capture technologies reduce relative production cost even in the absence of a carbon price, but this excludes the cost of CO2 transport and storage. Meanwhile, radical process transition pathways have a higher dependence on the future prices of natural gas, electricity, and scrap. Future work should focus on expanding the economic appraisal to other sectors and to indirect costs, as well as incorporating wider material efficiency strategies and running different future scenarios.
15

Utveckling för samverkansprocesser : En jämförande studie om hur implementeringsstrategier i ett urbant utvecklingsprojekt påverkade verksamheternas utveckling / Development for collaborative processes : A comparative study on how implementation strategies of an urban development project influenced organizational development

Karlstrand, Malin, Larsson, Erik, Nordström, Andreas January 2011 (has links)
Idag startas många projekt kring samverkan men de implementeras sällan i verksamheterna och ger således ingen bestående förändring. Ledarskapskompetens i samband med implementering av organisationsförändring har visat sig vara av stor betydelse. Storstadssatsningen är ett samverkansprojekt och projektet Bärkraft är en del i Storstadssatsningen, vilken startades i Borås för att utveckla samverkan mellan verksamheter i Brämhults kommundel. Samverkan behandlas i teorin som att viktiga attribut för lyckad samverkan är att vilja, kunna och förstå. Andra aspekter är hur samverkan mellan verksamheter byggs upp kring olika kategorier. Studiens syfte är att jämföra hur chefer inom två organisationer upplever att projektet Bärkraft inverkat på deras verksamheter och vidare om denna utveckling har mynnat ut i samverkansprocesser mellan de deltagande organisationerna i projektet. Vi ämnar också undersöka medarbetarnas upplevelser av hur cheferna har påverkat utvecklingen i verksamheten och om de upplever att en samverkansprocess har etablerats mellan de deltagande organisationerna.Studiens metod har en kvalitativ ansats där nio intervjuer har genomförts med fyra chefer och fem medarbetare i två organisationer. Intervjuerna spelades in, skrevs ut ordagrant och analyserades enligt marginalmetoden för att tolka och förstå respondenternas utsagor. I resultat av chefernas intervjuer kan vi utläsa att skillnader i utveckling och samverkan berott på olika förutsättningar verksamheterna har haft och det har påverkat deras arbetssätt. Det finns i medarbetarnas upplevelser skiljda meningar om i vilken utsträckning utveckling och samverkan skett, dock framhålls det som att det i viss mån lett till utveckling samt samverkan. I diskussionen har vi kommit fram till att det har funnits olika utgångspunkter och förutsättningar för verksamheterna arbete med det fortsatta utvecklingsarbetet. Vidare anses detta haft en väsentlig betydelse för att olika arbetsmetoder utvecklas för att inom verksamheten kunna arbeta med utveckling och samverkan. / Program: Organisations- och personalutvecklare i samhället
16

Functionality Based Refactoring: Improving Source Code Comprehension

Beiko, Jeffrey Lee 27 September 2007 (has links)
Thesis (Master, Computing) -- Queen's University, 2007-09-25 12:38:48.455 / Software maintenance is the lifecycle activity that consumes the greatest amount of resources. Maintenance is a difficult task because of the size of software systems. Much of the time spent on maintenance is spent trying to understand source code. Refactoring offers a way to improve source code design and quality. We present an approach to refactoring that is based on the functionality of source code. Sets of heuristics are captured as patterns of source code. Refactoring opportunities are located using these patterns, and dependencies are verified to check if the located refactorings preserve the dependencies in the source code. Our automated tool performs the functional-based refactoring opportunities detection process, verifies dependencies, and performs the refactorings that preserve dependencies. These refactorings transform the source code into a series of functional regions of code, which makes it easier for developers to locate code they are searching for. This also creates a chunked structure in the source code, which helps with bottom-up program comprehension. Thus, this process reduces the amount of time required for maintenance by reducing the amount of time spent on program comprehension. We perform case studies to demonstrate the effectiveness of our automated approach on two open source applications. / Master
17

Functionality based refactoring : improving source code comprehension

Beiko, Jeffrey Lee 02 January 2008 (has links)
Software maintenance is the lifecycle activity that consumes the greatest amount of resources. Maintenance is a difficult task because of the size of software systems. Much of the time spent on maintenance is spent trying to understand source code. Refactoring offers a way to improve source code design and quality. We present an approach to refactoring that is based on the functionality of source code. Sets of heuristics are captured as patterns of source code. Refactoring opportunities are located using these patterns, and dependencies are verified to check if the located refactorings preserve the dependencies in the source code. Our automated tool performs the functional-based refactoring opportunities detection process, verifies dependencies, and performs the refactorings that preserve dependencies. These refactorings transform the source code into a series of functional regions of code, which makes it easier for developers to locate code they are searching for. This also creates a chunked structure in the source code, which helps with bottom-up program comprehension. Thus, this process reduces the amount of time required for maintenance by reducing the amount of time spent on program comprehension. We perform case studies to demonstrate the effectiveness of our automated approach on two open source applications. / Thesis (Master, Computing) -- Queen's University, 2007-10-05 12:48:56.977
18

The Relationship Between Bottom-Up Saliency and Gaze Behaviour During Audiovisual Speech Perception

Everdell, IAN 12 January 2009 (has links)
Face-to-face communication is one of the most natural forms of interaction between humans. Speech perception is an important part of this interaction. While speech could be said to be primarily auditory in nature, visual information can play a significant role in influencing perception. It is not well understood what visual information is important or how that information is collected. Previous studies have documented the preference to gaze at the eyes, nose, and mouth of the talking face, but physical saliency, i.e., the unique low-level features of the stimulus, has not been explicitly examined. Two eye-tracking experiments are presented to investigate the role of physical saliency in the guidance of gaze fixations during audiovisual speech perception. Experiment 1 quantified the physical saliency of a talking face and examined its relationship with the gaze behaviour of participants performing an audiovisual speech perception task and an emotion judgment task. The majority of fixations were made to locations on the face that exhibited high relative saliency, but not necessarily the maximally salient location. The addition of acoustic background noise resulted in a change in gaze behaviour and a decrease in correspondence between saliency and gaze behaviour, whereas changing the task did not alter this correspondence despite changes in gaze behaviour. Experiment 2 manipulated the visual information available to the viewer by using animated full-feature and point-light talking faces. Removing static information, such as colour, intensity, and orientation, from the stimuli elicited both a change in gaze behaviour and a decrease in correspondence between saliency and gaze behaviour. Removing dynamic information, particularly head motion, resulted in a decrease in correspondence between saliency and gaze behaviour without any change in gaze behaviour. The results of these experiments show that, while physical saliency is correlated with gaze behaviour, it cannot be the single factor determining the selection of gaze fixations. Interactions within and between bottom-up and top-down processing are suggested to guide the selection of gaze fixations during audiovisual speech perception. / Thesis (Master, Neuroscience Studies) -- Queen's University, 2008-12-18 13:10:01.694
19

Trace gas and particulate matter emissions from road transportation in India quantification of current and future levels, uncertainties and sensitivity analysis

Baidya, Suman K. January 2008 (has links)
Zugl.: Stuttgart, Univ., Diss., 2008
20

Monitoring kritischer Prozess- und Projektaktivitäten mithilfe persönlicher Assistenten /

Winkler, Stefan. January 2010 (has links)
Zugl.: Erlangen-Nürnberg, Universiẗat, Diss., 2009.

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