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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.
1

Zhodnocení fauny epigeických pavouků (Araneida) NPP Malhotky

Smetanová, Eva January 2006 (has links)
No description available.
2

Unterstützung der ukrainischen Aufsichtsbehörde beim Ausbau der verbesserten betrieblichen KKW-Überwachung (Teil 3)

Beyer, Matthias, Carl, Helmar 31 March 2010 (has links) (PDF)
In Analogie zu den Systemen für die KKW Saporoshje und Rovno wurden für die drei Blöcke des KKW Südukraine und für den ersten Block des KKW Chmelnitzky technische Systeme zur verbesserten betrieblichen Überwachung eingerichtet. Dazu werden der Aufsichtsbehörde vor Ort und im Krisenzentrum in Kiew einmal pro Minute für jeden Block bis zu 51 sicherheitsrelevante technologische und 16 radiologische Parameter zur Bewertung mittels moderner technischer Ausrüstungen online zur Verfügung gestellt. Die entwickelte Auswertesoftware gestattet die Darstellung der Bewertungsergebnisse in Form von Tabellen, Grafiken und Schemata. Außerdem ermöglicht ein Archivmodus Trendanalysen. Mit der Integration der für die geschützte Warte gelieferten Ausrüstungen in das am Standort des KKW Saporoshje betriebene Fernüberwachungssystem ist es nunmehr möglich, die wesentlichen sicherheitsrelevanten Parameter des gesamten Standortes auch bei außergewöhnlichen Ereignissen mit Hilfe moderner Technik zu erfassen und zu bewerten.
3

Unterstützung der ukrainischen Aufsichtsbehörde beim Ausbau der verbesserten betrieblichen KKW-Überwachung (Teil 3)

Beyer, Matthias, Carl, Helmar January 2005 (has links)
In Analogie zu den Systemen für die KKW Saporoshje und Rovno wurden für die drei Blöcke des KKW Südukraine und für den ersten Block des KKW Chmelnitzky technische Systeme zur verbesserten betrieblichen Überwachung eingerichtet. Dazu werden der Aufsichtsbehörde vor Ort und im Krisenzentrum in Kiew einmal pro Minute für jeden Block bis zu 51 sicherheitsrelevante technologische und 16 radiologische Parameter zur Bewertung mittels moderner technischer Ausrüstungen online zur Verfügung gestellt. Die entwickelte Auswertesoftware gestattet die Darstellung der Bewertungsergebnisse in Form von Tabellen, Grafiken und Schemata. Außerdem ermöglicht ein Archivmodus Trendanalysen. Mit der Integration der für die geschützte Warte gelieferten Ausrüstungen in das am Standort des KKW Saporoshje betriebene Fernüberwachungssystem ist es nunmehr möglich, die wesentlichen sicherheitsrelevanten Parameter des gesamten Standortes auch bei außergewöhnlichen Ereignissen mit Hilfe moderner Technik zu erfassen und zu bewerten.
4

Säker identifiering via NFC

Eriksson, Daniel, Färg, Fredrik January 2013 (has links)
Near Field Communication (NFC) växer i popularitet och byggs in i allt fler mobiltelefoner. Den här rapporten beskriver hur man på ett säkert sätt identifierar en godkänd användare via NFC. NFC saknar helt skydd för det data som överförs via RF. Den i rapporten beskrivna identifieringsprocessen skyddar den överförda identiteten mot kopiering och säkerställer att avlyssning av kommunikationen mellan NFC enheterna inte gör det möjligt för en obehörig att imitera en behörig användare och därmed själv bli identifierad som behörig. Syftet med arbetet är att:  Undersöka om en NFC-enhet kan användas som nyckel för att starta en bil. Följande fråga kommer att besvaras i denna rapport:  Hur implementeras en säker överföring av en identitet via NFC? Som metod användes aktionsforskning vilket innebär att man efter teoretiska studier kommer fram till en eller flera möjliga lösningar på det problem ska lösas. Därefter genomförs praktiska experiment för att bekräfta eller avfärda lösningen eller för att jämföra olika lösningars för- och nackdelar. Slutligen dokumenteras resultaten. För att hitta möjliga lösningar till problemet studerades först hur kryptering och hashning fungerar och hur de kunde användas i den specifika tillämpningen. Även metoden med synkroniserade listor utvärderades. Det viktiga spörsmålet, att göra avlyssning och kopiering av kommunikationen verkningslös, löstes genom att säkerställa att varje meddelande som överför identiteten var unikt. Efter en teoretisk jämförelse av de olika metoderna valdes hashning av en saltad identitet ut att implementeras och testas. För att kunna genomföra de praktiska testerna utvecklades ett kretskort baserad på NFC-controllern PN532 med tillhörande programvara. Detta gjordes i två steg där vi först utvecklade protokollhanteringen i en 8-bitars enchipsdator och därefter anpassades koden till en mer avancerad Linuxdator. Protokollimplementeringen genomfördes med hjälp av tidigare examensarbete "Dataöverföring mellan en mobiltelefon och en NFC-läsare" av Linda Karlsson [1]. I det avslutande kapitlet diskuteras hur den i rapporten beskrivna lösningen kan utvecklas vidare genom att med hjälp av digitala certifikat distribuera rättigheter till NFC enheter. En fallstudie beskriver en tillämpning inom affärsområdet biluthyrning.
5

Estimating the Carbon Fluxes using the CASA Model in the Southern United States

Rongali, Venkata Narendra Appala 01 May 2010 (has links)
A minute change in human body temperature can get one collapsed permanently. If this is the case with human body, one might wonder what would be the case with Earth. The result is the greenhouse. The main function of the greenhouse gases (GHG’s) is to tap energy from the sun and prevent the heat energy escaping to space, thus sustaining life on earth. Because of increased human activity, industrialization, and deforestation, the concentration of the GHG’s in the atmosphere has increased, resulting in a temperature rise. Considering the effects of temperature rise, caused by the GHG’s, one should know the ways to minimize them. In order to do this, an estimation of the amount of GHG’s is important. The CASA model is one such model that estimate the GHG’s and also the amount of carbon in the atmosphere by estimating the Net Ecosystem Productivity (NEP) and Net Primary Productivity (NPP).
6

Monitoramento das pastagens cultivadas no cerrado goiano a partir de imagens MODIS índices de vegetação (MOD13Q1) / Monitoring cultivated pastures in the Cerrado Goiano Image from MODIS vegetation index (MOD13Q1)

GARCIA, Fanuel Nogueira 27 March 2012 (has links)
Made available in DSpace on 2014-07-29T15:32:05Z (GMT). No. of bitstreams: 1 DISSERTACAO_FANUEL_GEOG.pdf: 5225631 bytes, checksum: 17be1fcb54dcf706976140dca2f5dadb (MD5) Previous issue date: 2012-03-27 / Cattle ranching is extremely important for the economy of Brazil. This activity is characterized by the intensive explotation of pastures, which occupy a vast area of the Brazilian territory, i.e. approximately 150 million hectares. Currently, Brazil is the largest meat exporter in the world. Concerning its biomes, this occupation occurs mainly in the Cerrado, where the 546.251 km² of area under utilization correspond to about 37% of the total pasture area in the country. Among the states encompassed within the Cerrado limits, Goiás has the largest pasture occupation, over 38.7% of its area. In addition, it has one of the largest livestock, with about 21.3 millions of heads, producing, on average, 600.000 tons of meat a year. Within this context, arises the concern with the quality of the Goias state pastures, since several studies show that a large portion of these pastures are already degraded (i.e. low capacity), with low cattle occupation. This study, based on remote sensing data, as well as on spatial and census data, aimed at evaluating the quality of the pastures in Goias through the estimation of the net primary productivity (NPP). The distribution of pastures in relation to soil types, cattle occupation at the municipality level, infra-structure and location of the meat processing plants were considered as well. The productivity estimations were based on the MOD13Q1 vegetation index images (EVI), for the 2001 2009 period. The analysis of pasture distribution were conducted through the intersection of the derived NPP and the ancillary data mentioned above. The main conclusions of our study are: a) the highest NPP values are found in the central, southeast and extreme northeastern portions of Goias; b) the highest NPP values are related to the following soils: argissolos, cambissolos, neossolos and latossolos (Oxisols), respectively; c) the average cattle occupation in the Cerrado in Goias is usually low, around 1,07 heads per hectare; d) there are several municipalities (major cattle producers) which have the totality of their pastures severely degraded; e) there is no strict correlation between the location of meat processing plants and quality of pastures, as well as cattle occupation. Thus, the monitoring of pasture quality and the analysis of correlated factors are of great importance, as cattle ranching are responsible for the largest occupation of the Cerrado in Goias e for most of the wealth in the state. / A pecuária é uma atividade extremamente importante para a economia do Brasil. Essa atividade se caracteriza pela exploração extensiva das pastagens, ocupando vasta área do território, aproximadamente 150 milhões de hectares. Atualmente, o Brasil é o maior exportador de carne bovina no mundo. Em relação aos biomas brasileiros, essa ocupação ocorre principalmente no Cerrado, ocupando uma área de 546.251 km², o que representa cerca de 37% da área total de pastagens no país. Dentre os estados que compõem os limites do Cerrado, Goiás é o que possui maior ocupação por pastagens, com aproximadamente 38.7% de sua área. Além disso, tem um dos maiores rebanhos bovinos, com cerca de 21.3 milhões de cabeças de gado, produzindo em média, 600.000 toneladas de carne por ano. Diante desse contexto, surge a preocupação sobre a qualidade das pastagens cultivadas no estado de Goiás, uma vez que diversos estudos mostram que grandes partes dessas pastagens estão com algum nível de degradação (i.e. baixa capacidade de suporte) e baixa lotação bovina média. Esse estudo, baseado em dados de sensoriamento remoto orbital, bem como bases de dados espaciais e censitários, teve como objetivo avaliar a qualidade das pastagens em Goiás, a partir da estimativa de produtividade primária líquida da vegetação (NPP). A distribuição das pastagens em relação ao tipo de solo, lotação bovina por município, infra-estrutura e localização das plantas de processamento de carne foram considerados também. As estimativas de produtividade foram baseadas nas imagens MODIS13Q1 de índice de vegetação (EVI), para o período de 2001 - 2009. As análises da distribuição de pastagens foram conduzidas através da intersecção do NPP e os dados auxiliares mencionados acima. Os principais resultados desse trabalho são: a) os maiores valores de NPP são encontrados nas porções centrais, sudeste e extremo nordeste do estado de Goiás; b) os maiores índices de NPP estão associados aos seguintes solos: argissolos, cambissolos, neossolos e latossolos, respectivamente; c) a média de lotação bovina no Cerrado goiano em geral é baixa, gira em torno de 1,07 cabeças por hectares; d) há vários municípios (maiores produtores de gado) que estão com suas áreas de pastagens seriamente comprometidas; e) não há grandes correlações entre o local dos frigoríficos e a qualidade das pastagens, bem como a ocupação de gado. Assim, o monitoramento da qualidade das pastagens e a análise de fatores correlatos são de grande importância, pois a pecuária é responsável pela ocupação de maior parte do Cerrado goiano e geração de grandes riquezas para o estado.
7

Carbon dynamics in Arctic vegetation

Street, Lorna Elizabeth January 2011 (has links)
Rapid climate change in Arctic regions is of concern due to important feedbacks between the Arctic land surface and the global climate system. A large amount of organic carbon (C) is currently stored in Arctic soils; if decomposition is stimulated under warmer conditions additional release of CO2 could result in an accelerating feedback on global climate. The strength and direction of Arctic C cycle - climate feedbacks will depend on the growth response of vegetation; if plant growth increases some or all of the extra CO2 emissions may be offset. Currently the Arctic is thought to be a small net sink for CO2, the expected balance of terrestrial C sinks and sources in the future is unknown. In this thesis I explore some of the critical unknowns in current understanding of C cycle dynamics in Arctic vegetation. Quantifying gross primary productivity (GPP) over regional scales is complicated by large spatial heterogeneity in plant functional type (PFT) in Arctic vegetation. I use data from five Arctic sites to test the generality of a relationship between leaf area index (LAI) and canopy total foliar nitrogen (TFN). LAI and TFN are key drivers of GPP and are tightly constrained across PFTs in Low Arctic Alaska and Sweden, therefore greatly simplifying the task of up-scaling. I use data from Greenland, Barrow and Svalbard to asses the generality of the LAI-TFN relationship in predicting GPP at higher Arctic latitudes. Arctic ecosystems are unique among biomes in the large relative contribution of bryophytes (mosses, liverworts and hornworts) to plant biomass. The contribution of bryophytes to ecosystem function has been relatively understudied and they are poorly represented in terrestrial C models. I use ground based measurements in Northern Sweden to fill an existing data gap by quantifying CO2 fluxes from bryophytes patches in early spring and summer, and develop a simple model of bryophyte GPP. Using the model I compare bryophyte GPP to that of vascular plants before, during and after the summer growing season, finding that productive bryophyte patches can contribute up to 90 % of modelled annual GPP for typical vascular plant communities at the same site, and that the relative magnitude of bryophyte GPP is greatest in spring whilst the vascular plant canopy is still developing. Understanding how GPP relates to plant growth is important in relating remotely sensed increases in Arctic ‘greenness’ to changes in plant C stocks. I use a 13C pulselabelling techniques to follow the fate of recently fixed C in mixed vascular and bryophyte vegetation, with a focus on quantifying the contribution of bryophytes to ecosystem carbon use efficiency (CUE). I show that bryophytes contribute significantly to GPP in mixed vegetation, and act to increase ecosystem CUE. I highlight the importance of including bryophytes, which do not have roots, in aboveground: belowground partitioning schemes in C models. To further explore C turnover in bryophytes, I use the results of a second 13C labelling experiment to develop a model of C turnover in two contrasting Arctic mosses (Polytrichum piliferum and Sphagnum fuscum). I find significant differences in C turnover between Polytrichum piliferum which respires or translocates about 80 % of GPP, while Sphagnum fuscum respires 60 %. This analysis is the first to explicitly model differences in C partitioning between Arctic bryophyte species. Finally, I discuss the implications of each chapter for our understanding of Arctic C dynamics, and suggest areas for further research.
8

Plán péče o lokalitu Macháčkův háj (Velká stráň) v k.ú. Sedlec u Kutné Hory

Kupecká, Jana January 2018 (has links)
The goal of this diploma thesis is development of care plan for Macháčkův háj. The care plan was designed according to department of environment municipality of Kutná Hora. The diploma thesis contains description of location including is historical development. The care plan is designed according to 'Osnovy plánů péče o národní a přírodní rezervace, přírodní rezervace, národní přírodní památky, přírodní památky a jejich ochranná pásma'. The map outputs are made in Microstation, Series 3 and ArcGIS 10.
9

Assessing the Impact of Nightlight Gradients on Street Robbery and Burglary in Cincinnati, Ohio

Zhou, Hanlin 15 June 2020 (has links)
No description available.
10

Modelling Net Primary Productivity and Above-Ground Biomass for Mapping of Spatial Biomass Distribution in Kazakhstan

Eisfelder, Christina 21 August 2013 (has links) (PDF)
Biomass is an important ecological variable for understanding the responses of vegetation to the currently observed global change. The impact of changes in vegetation biomass on the global ecosystem is also of high relevance. The vegetation in the arid and semi-arid environments of Kazakhstan is expected to be affected particularly strongly by future climate change. Therefore, it is of great interest to observe large-scale vegetation dynamics and biomass distribution in Kazakhstan. At the beginning of this dissertation, previous research activities and remote-sensing-based methods for biomass estimation in semi-arid regions have been comprehensively reviewed for the first time. The review revealed that the biggest challenge is the transferability of methods in time and space. Empirical approaches, which are predominantly applied, proved to be hardly transferable. Remote-sensing-based Net Primary Productivity (NPP) models, on the other hand, allow for regional to continental modelling of NPP time-series and are potentially transferable to new regions. This thesis thus deals with modelling and analysis of NPP time-series for Kazakhstan and presents a methodological concept for derivation of above-ground biomass estimates based on NPP data. For validation of the results, biomass field data were collected in three study areas in Kazakhstan. For the selection of an appropriate model, two remote-sensing-based NPP models were applied to a study area in Central Kazakhstan. The first is the Regional Biomass Model (RBM). The second is the Biosphere Energy Transfer Hydrology Model (BETHY/DLR). Both models were applied to Kazakhstan for the first time in this dissertation. Differences in the modelling approaches, intermediate products, and calculated NPP, as well as their temporal characteristics were analysed and discussed. The model BETHY/DLR was then used to calculate NPP for Kazakhstan for 2003–2011. The results were analysed regarding spatial, intra-annual, and inter-annual variations. In addition, the correlation between NPP and meteorological parameters was analysed. In the last part of this dissertation, a methodological concept for derivation of above-ground biomass estimates of natural vegetation from NPP time-series has been developed. The concept is based on the NPP time-series, information about fractional cover of herbaceous and woody vegetation, and plants’ relative growth rates (RGRs). It has been the first time that these parameters are combined for biomass estimation in semi-arid regions. The developed approach was finally applied to estimate biomass for the three study areas in Kazakhstan and validated with field data. The results of this dissertation provide information about the vegetation dynamics in Kazakhstan for 2003–2011. This is valuable information for a sustainable land management and the identification of regions that are potentially affected by a changing climate. Furthermore, a methodological concept for the estimation of biomass based on NPP time-series is presented. The developed method is potentially transferable. Providing that the required information regarding vegetation distribution and fractional cover is available, the method will allow for repeated and large-area biomass estimation for natural vegetation in Kazakhstan and other semi-arid environments.

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