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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.
51

Hybrid Model Approach to Appliance Load Disaggregation : Expressive appliance modelling by combining convolutional neural networks and hidden semi Markov models. / Hybridmodell för disaggregering av hemelektronik : Detaljerad modellering av elapparater genom att kombinera neurala nätverk och Markovmodeller.

Huss, Anders January 2015 (has links)
The increasing energy consumption is one of the greatest environmental challenges of our time. Residential buildings account for a considerable part of the total electricity consumption and is further a sector that is shown to have large savings potential. Non Intrusive Load Monitoring (NILM), i.e. the deduction of the electricity consumption of individual home appliances from the total electricity consumption of a household, is a compelling approach to deliver appliance specific consumption feedback to consumers. This enables informed choices and can promote sustainable and cost saving actions. To achieve this, accurate and reliable appliance load disaggregation algorithms must be developed. This Master's thesis proposes a novel approach to tackle the disaggregation problem inspired by state of the art algorithms in the field of speech recognition. Previous approaches, for sampling frequencies <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Cleq" />1 Hz, have primarily focused on different types of hidden Markov models (HMMs) and occasionally the use of artificial neural networks (ANNs). HMMs are a natural representation of electric appliances, however with a purely generative approach to disaggregation, basically all appliances have to be modelled simultaneously. Due to the large number of possible appliances and variations between households, this is a major challenge. It imposes strong restrictions on the complexity, and thus the expressiveness, of the respective appliance model to make inference algorithms feasible. In this thesis, disaggregation is treated as a factorisation problem where the respective appliance signal has to be extracted from its background. A hybrid model is proposed, where a convolutional neural network (CNN) extracts features that correlate with the state of a single appliance and the features are used as observations for a hidden semi Markov model (HSMM) of the appliance. Since this allows for modelling of a single appliance, it becomes computationally feasible to use a more expressive Markov model. As proof of concept, the hybrid model is evaluated on 238 days of 1 Hz power data, collected from six households, to predict the power usage of the households' washing machine. The hybrid model is shown to perform considerably better than a CNN alone and it is further demonstrated how a significant increase in performance is achieved by including transitional features in the HSMM. / Den ökande energikonsumtionen är en stor utmaning för en hållbar utveckling. Bostäder står för en stor del av vår totala elförbrukning och är en sektor där det påvisats stor potential för besparingar. Non Intrusive Load Monitoring (NILM), dvs. härledning av hushållsapparaters individuella elförbrukning utifrån ett hushålls totala elförbrukning, är en tilltalande metod för att fortlöpande ge detaljerad information om elförbrukningen till hushåll. Detta utgör ett underlag för medvetna beslut och kan bidraga med incitament för hushåll att minska sin miljöpåverakan och sina elkostnader. För att åstadkomma detta måste precisa och tillförlitliga algoritmer för el-disaggregering utvecklas. Denna masteruppsats föreslår ett nytt angreppssätt till el-disaggregeringsproblemet, inspirerat av ledande metoder inom taligenkänning. Tidigare angreppsätt inom NILM (i frekvensområdet <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Cleq" />1 Hz) har huvudsakligen fokuserat på olika typer av Markovmodeller (HMM) och enstaka förekomster av artificiella neurala nätverk. En HMM är en naturlig representation av en elapparat, men med uteslutande generativ modellering måste alla apparater modelleras samtidigt. Det stora antalet möjliga apparater och den stora variationen i sammansättningen av dessa mellan olika hushåll utgör en stor utmaning för sådana metoder. Det medför en stark begränsning av komplexiteten och detaljnivån i modellen av respektive apparat, för att de algoritmer som används vid prediktion ska vara beräkningsmässigt möjliga. I denna uppsats behandlas el-disaggregering som ett faktoriseringsproblem, där respektive apparat ska separeras från bakgrunden av andra apparater. För att göra detta föreslås en hybridmodell där ett neuralt nätverk extraherar information som korrelerar med sannolikheten för att den avsedda apparaten är i olika tillstånd. Denna information används som obervationssekvens för en semi-Markovmodell (HSMM). Då detta utförs för en enskild apparat blir det beräkningsmässigt möjligt att använda en mer detaljerad modell av apparaten. Den föreslagna Hybridmodellen utvärderas för uppgiften att avgöra när tvättmaskinen används för totalt 238 dagar av elförbrukningsmätningar från sex olika hushåll. Hybridmodellen presterar betydligt bättre än enbart ett neuralt nätverk, vidare påvisas att prestandan förbättras ytterligare genom att introducera tillstånds-övergång-observationer i HSMM:en.
52

Contemporary Measurements of Poverty : Does Modern Poverty Measurement instances fully consider the complexities of gender Dimensions?

Strandgård, Marcus January 2022 (has links)
This essay concerns itself with the measurement of poverty. Through a lens of gender sensitivity, combined with three dimensions of gender, this essay analyses the quality of various SDG indicators. The paper has incorporated a methodology based on a qualitative content analysis, this method proves as an excellent way to analyse the strength of indicators relating to the SDG:s, as well as proves to work in symbiosis with the analytical framework of this essay. Through the analysis of this essay, it has been concluded that the instances as the SDG:s measure poverty proves to be insufficient. As the overall quality, combined with in some instances, the quantity of measurement instances holds sub-standard characteristics, the goal of leaving no one behind proves to be quite difficult to overcome.
53

Resource Description Diagram Supplement to “Cataloging Theory in Search of Graph Theory and Other Ivory Towers. Object: Cultural Heritage Resource Description Networks.”

Murray, Ronald J., Tillett, Barbara B. 15 August 2011 (has links)
These documents supplement the previously deposited Murray and Tillett working paper: “Cataloging Theory in Search of Graph Theory and Other Ivory Towers. Object: Cultural Heritage Resource Description Networks.” http://hdl.handle.net/10150/136270. A different version of Fig 8, “FRBR Paper Tool Diagram Elements And Graphs” is included. Documents not referenced in the paper include: “Modeling The Superwork Issue,” which models the concept of a Work composed of other Works two ways; “Progressive Disaggregation,” which demonstrates the recursive process by which simple resource and descriptions composed of other descriptions are resolved to elementary graph structures; and “Serial Publication,” which highlights the pedagogical and IT system guidance role that FRBR resource description diagrams can play with respect to complex publishing phenomena. A “Find & Navigate” diagram element has been introduced in the serial publication diagram as a theoretical necessity with practical implications. The elements provide a consistent means for depicting the linking functions provided by identifiers, name and subject authority records, and prescribed and arbitrary relationships. The tables and legends found on the right side of the diagram suggest how diagram components may be expressed as “triple” style statements for implementation-minded readers.
54

Desagregação do modo de entrada : internacionalização da cadeia global de valor das empresas exportadoras / Disaggregation of the mode of entry: internationalization of the global value chain of exporting companies

Marinho, Ana Paula Lopes 12 December 2017 (has links)
Submitted by Adriana Alves Rodrigues (aalves@espm.br) on 2018-05-30T16:17:13Z No. of bitstreams: 1 Ana Paula Lopes Marinho_SEM CORREÇÃO.pdf: 1214456 bytes, checksum: d293fc6403b539cac1bc495ed4a5cdd7 (MD5) / Approved for entry into archive by Adriana Alves Rodrigues (aalves@espm.br) on 2018-05-30T16:17:43Z (GMT) No. of bitstreams: 1 Ana Paula Lopes Marinho_SEM CORREÇÃO.pdf: 1214456 bytes, checksum: d293fc6403b539cac1bc495ed4a5cdd7 (MD5) / Approved for entry into archive by Adriana Alves Rodrigues (aalves@espm.br) on 2018-05-30T17:50:54Z (GMT) No. of bitstreams: 1 Ana Paula Lopes Marinho_SEM CORREÇÃO.pdf: 1214456 bytes, checksum: d293fc6403b539cac1bc495ed4a5cdd7 (MD5) / Made available in DSpace on 2018-05-30T18:05:01Z (GMT). No. of bitstreams: 1 Ana Paula Lopes Marinho_SEM CORREÇÃO.pdf: 1214456 bytes, checksum: d293fc6403b539cac1bc495ed4a5cdd7 (MD5) Previous issue date: 2017-12-12 / This research deals with one of the theoretical approaches to international business to demonstrate how exporters are behaving in the foreign market. The main challenge of this study was to investigate the implementation of its new product development activities in other countries to see if part of the process can assume global configuration from the strategic combination of entry mode. The theories that were relevant to this empirical study highlight the theoretical advances on (1) the internationalization of the company's operations (Hymer, 1960; Vernon, 1966; Williamson 1971, 1975; Buckley & Casson 1976; Johanson & Vahlne 1977; Barter & Hesterly, 2008), which can be used to determine the value chain in the development of technology (Porter, 1990; Roter & Norman, 1990; Wen-Cheng et al., 2011; Casson et al., 2016) and (3) innovation and the evolution of models of innovation systems (Cooper, 1990, 2006, Von Zedtwitz, Birkinshaw, 2007; Keegan, 1997; Wheelwright & Clark, 1992a). The theoretical reference was selected with the purpose of combining the consistent aspects between them and integrating the approaches to the explanation of the phenomenon under analysis. The hypothesis considered is that the stages of conceptualization, development and testing of exporters' products can be carried out globally in a disaggregated way and not only in the local market. The type of the research is exploratory, quantitative approach, using the survey method. The results of this investigation showed that different mechanisms of interaction at different borders are enabling exporters to develop new product development practices in the exterior in a disaggregated way. Therefore, our main contribution is to present new theoretical perspectives that even the company classified as an exporter, that is, a beginner in the international market, can have advanced levels of internationalization in one of the stages of the value chain, in opposition to the literature of internationalization that defends the gradual entry into international markets. The study may contribute to the managers of the organizations to explore new product development activities in a decentralized way abroad. / Esta pesquisa trata uma das abordagens teóricas de negócios internacionais para demonstrar como as exportadoras estão se comportando no mercado externo. O principal desafio deste estudo foi investigar a execução de suas atividades de desenvolvimento de novos produtos em outros países para verificar se parte do processo podem assumir configuração global a partir da combinação estratégicas de modo de entrada. As teorias que se mostraram relevantes para este estudo empírico ressaltam os avanços teóricos sobre (1) internacionalização das operações da empresa (Hymer, 1960; Vernon, 1966; Williamson, 1971, 1975; Buckley & Casson, 1976; Johanson &Vahlne, 1977; 1990; Rugman, 1980; Dunning, 1981; Porter, 1990; Knight & Cavusgil, 2015), (2) cadeia de valor com ênfase em desenvolvimento de tecnologia (Porter 1986, 1990; Rozhan & Norman, 2011; Barney & Hesterly, 2008; 1990; Wen-Cheng et al., 2011; Casson et al., 2016) e (3) inovação e a evolução dos modelos dos sistemas de inovação (Cooper, 1990; 2006; Von Zedtwitz, 2015; Chesbrough, 2007, Hansen & Birkinshaw, 2007; Keegan, 1997; Wheelwright & Clark, 1992ª). O referencial teórico foi selecionado com o propósito de combinar os aspectos consistentes entre si e integrar as abordagens à explicação do fenômeno em análise. A hipótese considerada é de que as etapas de conceitualização, desenvolvimento e testes do produto das exportadoras podem ser realizadas globalmente de forma desagregada e não apenas no mercado local. O tipo da pesquisa é exploratória, abordagem quantitativa, utilizando-se o método survey. Os resultados desta investigação mostraram que diferentes mecanismos de interação em diferentes fronteiras estão possibilitando que as exportadoras realizemno exterior práticas de desenvolvimento de novos produtos de forma desagregada. Logo, nossa principal contribuição é apresentar novas perspectivas teóricas de que mesmo a empresa classificada como exportadora, ou seja, iniciante no mercado internacional, podem ter níveis avançados de internacionalização em uma das etapas da cadeia de valor, contrapondo a literatura de internacionalização que defende a entrada de forma gradual em mercados internacionais. O estudo pode contribuir com os gestores das organizações a explorarem no exterior as atividades de desenvolvimento de novos produtos de forma descentralizada.
55

Disaggregation of Electrical Appliances using Non-Intrusive Load Monitoring / Classification des équipements électriques par le monitoring non-intrusif des charges

Bier, Thomas 17 December 2014 (has links)
Cette thèse présente une méthode pour désagréger les appareils électriques dans le profil des bâtiments résidentiels de charge. Au cours des dernières années, la surveillance de l’énergie a obtenu beaucoup de popularité dans un environnement privé et industriel. Avec des algorithmes de la désagrégation, les données mesurées à partir de soi-disant compteurs intelligents peuvent être utilisés pour fournir de plus amples informations de la consommation d’énergie. Une méthode pour recevoir ces données est appelé non-intrusifs charge identification. La majeure partie de la thèse peut être divisée en trois parties. Dans un premier temps, un système de mesure propre a été développé et vérifié. Avec ce système, les ensembles de données réelles peuvent être générés pour le développement et la vérification des algorithmes de désagrégation. La deuxième partie décrit le développement d’un détecteur de flanc. Différentes méthodes sont présentées et évaluées, avec lequel les temps de commutation des appareils peuvent être détectés dans le profil de la charge. La dernière partie décrit un procédé de classification. Différents critères sont utilisés pour la classification. Le classificateur reconnaît et étiquette les appareils individuels de la courbe de charge. Pour les classifications différentes structures de réseaux de neurones artificiels sont comparés. / This thesis presents a method to disaggregate electrical appliances in the load profile of residential buildings. In recent years, energy monitoring has obtained significantly popularity in private and industrial environment. With algorithms of the disaggregation, the measured data from so-called smart meters can be used to provide more information of the energy usage. One method to receive these data is called non-intrusive appliance load monitoring.The main part of the thesis can be divided into three parts. At first, an own measurement system was developed and verified. With that system, real data sets can be generated for the development and verification of the disaggregation algorithms. The second part describes the development of an event detector. Different methods are presented and evaluated, with which the switching times of the appliances can be detected in the load profile. The last part describes a classification method. Different features are used for the classification. The classifier recognizes and labels the individual appliances in the load profile. For the classification different structures of artificial neural network (ANN) are compared.
56

Climate change assessment for the southeastern United States

Zhang, Feng 11 August 2011 (has links)
Water resource planning and management practices in the southeastern United States may be vulnerable to climate change. This vulnerability has not been quantified, and decision makers, although generally concerned, are unable to appreciate the extent of the possible impact of climate change nor formulate and adopt mitigating management strategies. Thus, this dissertation aims to fulfill this need by generating decision worthy data and information using an integrated climate change assessment framework. To begin this work, we develop a new joint variable spatial downscaling technique for statistically downscaling gridded climatic variables to generate high-resolution, gridded datasets for regional watershed modeling and assessment. The approach differs from previous statistical downscaling methods in that multiple climatic variables are downscaled simultaneously and consistently to produce realistic climate projections. In the bias correction step, JVSD uses a differencing process to create stationary joint cumulative frequency statistics of the variables being downscaled. The functional relationship between these statistics and those of the historical observation period is subsequently used to remove GCM bias. The original variables are recovered through summation of bias corrected differenced sequences. In the spatial disaggregation step, JVSD uses a historical analogue approach, with historical analogues identified simultaneously for all atmospheric fields and over all areas of the basin under study. In the second component of the integrated assessment framework, we develop a data-driven, downward hydrological watershed model for transforming the climate variables obtained from the downscaling procedures to hydrological variables. The watershed model includes several water balance elements with nonlinear storage-release functions. The release functions and parameters are data driven and estimated using a recursive identification methodology suitable for multiple, inter-linked modeling components. The model evolves from larger spatial/temporal scales down to smaller spatial/temporal scales with increasing model structure complexity. For ungauged or poorly-gauged watersheds, we developed and applied regionalization hydrologic models based on stepwise regressions to relate the parameters of the hydrological models to observed watershed responses at specific scales. Finally, we present the climate change assessment results for six river basins in the southeastern United States. The historical (baseline) assessment is based on climatic data for the period 1901 through 2009. The future assessment consists of running the assessment models under all IPCC A1B and A2 climate scenarios for the period from 2000 through 2099. The climate assessment includes temperature, precipitation, and potential evapotranspiration; the hydrology assessment includes primary hydrologic variables (i.e., soil moisture, evapotranspiration, and runoff) for each watershed.
57

[en] DISAGGREGATION POWER MODEL AND FLOWS AND LOSS ESTIMATION APPLIED FOR SUBTRANSMISSION SYSTEM / [pt] MODELO DE DESAGREGAÇÃO DE POTÊNCIAS, ESTIMAÇÃO DE FLUXOS E PERDAS TÉCNICAS EM SISTEMAS DE SUBTRANSMISSÃO

SERGIO ALONSO ALVAREZ CARDENAS 25 May 2018 (has links)
[pt] A estimação dos fluxos de potência e perdas técnicas nos sistemas de subtransmissão é um grande desafio para as distribuidoras pela importância no planejamento e operação do sistema. Por isso, surge a necessidade de contar com modelos que permitam simular estas grandezas, para o adequado planejamento do sistema. Neste trabalho é proposto e implementado um modelo de estimação de fluxos de potência e perdas técnicas em um sistema de subtransmissão baseado na desagregação de potência da demanda importada da rede de transmissão. A metodologia envolve a determinação de fatores de desagregação por barra associados à importação total de potência, estimação dos fluxos de potência DC usando a matriz de sensibilidade ramo-barra caraterística da rede elétrica e, finalmente, a estimação das perdas elétricas. O sistema IEEE 24 barras foi utilizado para o caso de estudo. Neste caso, a rede elétrica de 230 kV foi tratada como a rede de transmissão e a rede de 138 kV como a rede de subtransmissão. Dados de geração e carga realistas, com base horária e ao longo de um ano, foram utilizados para estimar os parâmetros dos modelos. Para avaliar os resultados, foram utilizadas métricas estatísticas e os resultados foram comparados com um modelo puramente estatístico, que correlaciona a importação total com as potências injetadas em cada barra, os fluxos nas linhas e as perdas totais. Os resultados obtidos indicaram que o modelo proposto ganha importância quando é possível controlar algumas injeções da rede elétrica, tornando-o mais dependente da rede elétrica. / [en] The estimation of the power flows and technical losses in the subtransmission systems is a great challenge for electricity distribution companies because of their importance in the planning and operation of the system. Therefore, there is the increasing need to have models that allow to simulate these variables for the proper planning of the system. In this work, a model of estimation of power flows and technical losses in a subtransmission system is proposed and implemented; this model is based on the power disaggregation of the imported demand from the transmission network. The methodology involves the determination of buses disaggregation factors associated with total power import, estimation of DC power flows using the bus-branch sensitivity matrix of the network and finally the estimation of the electrical losses. The IEEE 24 bus system was used for this study case. In this case, the 230 kV power grid was treated as the transmission network and the 138 kV network as the subtransmission network. Realistic generation and loading data, based on hourly time and over the span of a year, were used to estimate the parameters of the models. In order to evaluate the results, statistical metrics were used and the results were compared with a purely statistical model, which correlates the total imports with the injected power in each bus, line flows and total losses. The obtained results indicate that the proposed model gains importance when it is possible to control some of the injections into the power grid, turning it more dependent of the power grid.
58

Erodibilidade de solos tropicais não saturados nos municípios de Senador Canedo e Bonfinópolis - GO / Analyzes of the erodibility in tropical and unsaturated soils in the municipalities of Bonfinópolis and Senador Canedo - GO

Almeida, João Guilherme Rassi 26 September 2014 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-01-27T14:17:38Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - João Guilherme Rassi Almeida - 2014.pdf: 5543352 bytes, checksum: a34c198e41193488cf976a151433c9a8 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-01-28T12:05:42Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - João Guilherme Rassi Almeida - 2014.pdf: 5543352 bytes, checksum: a34c198e41193488cf976a151433c9a8 (MD5) / Made available in DSpace on 2015-01-28T12:05:42Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - João Guilherme Rassi Almeida - 2014.pdf: 5543352 bytes, checksum: a34c198e41193488cf976a151433c9a8 (MD5) Previous issue date: 2014-09-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Environment, socials and economics problems are related with erosive process, like: loss of soil productivity, silting of rivers and lakes, landslides in areas of risk and commitment of public services. Aspects such as climate, topography, soil type and the use and occupation of land by humans are decisive in understanding the susceptibility of a site to water erosion. However, in the case of tropical regions, two aspects have relative importance in studies erodibility: non saturation and weathering degree. In this way, the present study aims to analyze the suction effect and laterization degree in erodibility soil, emphasizing important parameters for carried out erodibility tests. Therefore, were selected two (02) areas near the city of Goiânia with distinct pedogenetic characteristics, one with younger soils (or even intermediate, as observed during the study) and another where weathering processes acted more intense, corresponding to a Cambisol soil type and a Oxisol type, respectively. In each site were collected disturbed and undisturbed samples with the aim to perform characterization tests, tropical soils tests, soil water retention curves and erodibility tests. On results were noted that both samples are a lateritic soils, presenting even primary minerals and iron oxides. The adjusting of soil water retention curves results on a bimodal shape for the Oxisol type due to the presence of micro and macropores, and with heterogeneous distribution shape for Cambisol Type, due the presence of grains on different sizes. At finally, the analysis of erosion, in general, results that the samples with lower initial suctions were more resistance to laminar erosions and in the processes of slope stability when submerged. On the Inderbitzen tests, the Oxisol showed be more susceptible to the erosive processes than the Cambisol type, probably because of the lower flow of the water. In the total and partial disintegration test, the samples of Oxisol demonstrate to be a good cohesive soil, opposite behavior have the Cambisol samples. / Os processos erosivos são fenômenos que envolvem sérios problemas ambientais, sociais e econômicos, tais como: perda da produtividade dos solos, assoreamentos de rios e lagos, deslizamentos em áreas de risco e o comprometimento de serviços públicos. Aspectos como o clima, o relevo, o tipo de solo e o uso e ocupação do solo pelo homem são determinantes no entendimento da suscetibilidade de um terreno aos processos erosivos hídricos. Contudo, em se tratando de regiões tropicais, dois aspectos apresentam relevante importância nos estudos de erodibilidade: a não saturação e o grau de intemperização. Desta forma, o presente estudo tem como objetivo geral a análise da influência da sucção e do grau de laterização na erodibilidade dos solos, destacando parâmetros importantes para a realização de ensaios de erodibilidade. Foram selecionadas 02 (duas) regiões próximas ao município de Goiânia com características pedogenéticas distintas, uma com ocorrência de solos jovens (ou mesmo intermediário, conforme foi constatado) e outra onde os processos de intemperismo agiram mais intensificadamente, correspondentes a um solo do tipo Cambissolo e do tipo Latossolo, respectivamente. Em cada local foram coletadas amostras deformadas e indeformadas com a finalidade de realizar ensaios de caracterização convencional e específicos para solos tropicais, curvas características solo-água e ensaios de erodibilidade dos solos. Como resultado, obteve-se que ambos os solos são lateríticos, apresentando desde minerais primários até óxidos e hidróxidos de ferro e alumínio. A curva característica solo-água resultou em formato bimodal para o Latossolo, devido à presença de micro e macroporos, e com distribuição heterogênea para o Cambissolo, devido à presença de grãos de variados tamanhos. Por fim, na análise dos processos erosivos, constatou-se que, em geral, as amostras com menores valores de sucções iniciais apresentaram-se mais resistentes à erodibilidade superficial e à estabilidade quando inundados. No ensaio de Inderbitzen a amostra de Latossolo demonstrou-se mais susceptível aos processos erosivos laminares do que a amostra de Cambissolo, devido à baixa vazão do fluxo de água. Já no ensaio de desagregação total e parcial, as amostras do Latossolo apresentaram-se bem coesas, ao contrário do ocorrido nas amostras do Cambissolo.
59

Erzeugung meteorolgischer Stundendaten: Entwicklung eines Wettergenerators zur zeitlichen Disaggregierung von Tages- auf Stundenwerte

Pluntke, Thomas, Kronenberg, Rico, Bernhofer, Christian 06 July 2020 (has links)
Die Publikation beschreibt den Aufbau und die Arbeitsweise eines Wettergenerators, der in der Lage ist, für einen Großteil von Witterungsbedingungen plausible und über alle Klimaelemente konsistente Stundendaten zu erzeugen. Er kann auf beliebige Klimastationen (bzw. Rasterzellen) angewendet werden. Damit wird dem Problem der für lange Zeiträume geringen flächenhaften Informationsdichte für meteorologische Daten in Stundenauflösung begegnet. Meteorologische Daten in stündlicher Auflösung werden für Anwendungen, wie z. B. die Hochwasser- oder Erosionsmodellierung, benötigt. Der Wettergenerator und das Nutzerhandbuch sind über das Regionale Klimainformationssystem ReKIS frei zugänglich. Redaktionsschluss: 05.04.2019
60

Utilization of Legacy Soil Data for Digital Soil Mapping and Data Delivery for the Busia Area, Kenya

Joshua O Minai (8071856) 06 December 2019 (has links)
Much older soils data and soils information lies idle in libraries and archives and is largely unused, especially in developing countries like Kenya. We demonstrated the usefulness of a stepwise approach to bring legacy soils data ‘back to life’ using the 1980 <i>Reconnaissance Soil Map of the Busia Area</i> <i>(quarter degree sheet No. 101)</i> in western Kenya as an example. Three studies were conducted by using agronomic information, field observations, and laboratory data available in the published soil survey report as inputs to several digital soil mapping techniques. In the first study, the agronomic information in the survey report was interpreted to generate 10 land quality maps. The maps represented the ability of the land to perform specific agronomic functions. Nineteen crop suitability maps that were not previously available were also generated. In the second study, a dataset of 76 profile points mined from the survey report was used as input to three spatial prediction models for soil organic carbon (SOC) and texture. The three predictions models were (i) ordinary kriging, (ii) stepwise multiple linear regression, and (iii) the Soil Land Inference Model (SoLIM). Statistically, ordinary kriging performed better than SoLIM and stepwise multiple linear regression in predicting SOC (RMSE = 0.02), clay (RMSE = 0.32), and silt (RMSE = 0.10), whereas stepwise multiple linear regression performed better than SoLIM and ordinary kriging for predicting sand content (RSME = 0.11). Ordinary kriging had the narrowest 95% confidence interval while stepwise multiple linear regression had, the widest. From a pedological standpoint, SoLIM conformed better to the soil forming factors model than ordinary kriging and had a narrower confidence interval compared to stepwise multiple linear regression. In the third study, rules generated from the map legend and map unit descriptions were used to generate a soil class map. Information about soil distribution and parent material from the map unit polygon descriptions were combined with six terrain attributes, to generate a disaggregated fuzzy soil class map. The terrain attributes were multiresolution ridgetop flatness (MRRTF), multiresolution valley bottom flatness (MRVBF), topographic wetness index (TWI), topographic position index (TPI), planform curvature, and profile curvature. The final result was a soil class map with a spatial resolution of 30 m, an overall accuracy of 58% and a Kappa coefficient of 0.54. Motivated by the wealth of soil agronomic information generated by this study, we successfully tested the feasibility of delivering this information in rural western Kenya using the cell phone-based Soil Explorer app (<a href="https://soilexplorer.net/">https://soilexplorer.net/</a>). This study demonstrates that legacy soil data can play a critical role in providing sustainable solutions to some of the most pressing agronomic challenges currently facing Kenya and most African countries.<div><p></p></div>

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