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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.
461

Protocolo ISO 11783: procedimentos para comunicação serial de dados do controlador de tarefa / ISO 11783 protocol: procedures for serial data communication with the task controller

Robson Rogério Dutra Pereira 29 January 2009 (has links)
O recente crescimento da utilização de tecnologias de automação e eletrônica embarcada em máquinas e implementos agrícolas tem estabelecido uma nova prática na área agrícola. Estas novas práticas relacionadas com a agricultura de precisão (AP) têm demandado a utilização de sensores e redes de comunicação embarcadas para aquisição de dados e controle dos dispositivos em campo. A incompatibilidade entre equipamentos e formatos de dados tornou-se um grande obstáculo. A tendência global é de uso de sistemas padronizados de acordo com a norma ISO 11783 (também conhecida como ISOBUS) nos dispositivos, ou Electronic Control Unit (ECU), utilizados na produção agrícola. No Brasil, essas ferramentas ainda não são largamente aplicadas. O objetivo deste trabalho é sistematizar as informações necessárias dos procedimentos para comunicação de uma ECU do implemento com a ECU de trator de gerenciamento. Focou-se no desenvolvimento dos arquivos padrões necessários e no programa da ECU do implemento, e testes de validação da comunicação dos dispositivos via rede ISO 11873. Estabeleceu-se a relação entre as informações sistematizadas e os dispositivos embarcados em máquinas agrícolas. Os dispositivos embarcados consistem em cinco ECUs interconectadas pela rede ISO 11783. Quatro ECUS estão localizados no tractor: ECU do GPS, Controlador de Tarefas (TC), Terminal Virtual (VT) e ECU do Trator (TECU). A ECU do GPS é responsável pela recepção do sinal do Differencial Global Position System (DGPS) e disponibilização na rede ISO 11783. O TC é responsável pelo gerenciamento da aplicação do mapa de prescrição e pelo controle do implemento. O VT é responsável por monitorar e disponibilizar uma interface gráfica com o operador da máquina. O TECU disponibiliza a velocidade do trator obtida por um sensor de radar. A quinta ECU está localizado no implemento, definido como Working Set Master (WSM), que é responsável por interpretar os comandos das ECUs do trator e integrar o dispositivo mecânico-hidráulico para realização de uma aplicação agrícola. Este trabalho mostrou os requisitos necessários para o desenvolvimento dos arquivos necessários (TaskData.XML e o Device Description Object Pool), as capacidades necessárias para o programa da ECU do Implemento, a validação da comunicação da ECU do Implemento com o TC (ECU do trator de gerenciamento) e comprovou que as informações sistematizadas facilitaram e proporcionaram a implementação de um sistema ISO 11783. Espera-se, que este trabalho possa abrir oportunidades para que a norma ISO 11783 possa ser melhor entendida e ampliar a possibilidade de disponibilizar um número maior de aplicações que envolvem o conceito de AP no Brasil. / The recent growth of automation technology and embedded electronic in agricultural machinery has established a new practice in agriculture. These new practices related to precision agriculture (PA) have demanded the use of sensors and communications embedded networks for data acquisition and control devices in the farm field. The incompatibility between hardware, software and data formats has become a major obstacle. The global trend is to use standardized systems in accordance with ISO 11783 (also known as ISOBUS) in the devices, or Electronic Control Units (ECU), used in agricultural production. In Brazil, these tools are not yet implemented. The purpose of this work is to systemize the information necessary of the procedures for communication among the implement ECU with management tractor ECU. This work focuses standardized files format, the program of the implement ECU and the validation tests of the devices communication via ISO 11873 network. It was established the relation among the systematized information and embedded devices on agricultural machinery. The embedded devices consist in five ECUs connected in the ISO 11783 network. Four ECUs are located in the tractor: GPS ECU, Task Controller (TC), Virtual Terminal (VT) and Tractor ECU (TECU). The GPS ECU is responsible to the Differential Global Positioning System (DGPS) positioning. The TC is responsible to manage the prescription map and to control the implement. The VT is responsible monitor the application. The TECU disposes tractor velocity of a radar sensor. The fifth device located in the implement is Working Set Master (WSM), which is responsible to interpret the commands from the tractors ECUs and integrate the mechanical-hidraulical device instruction for agricultural operation. It was presented how to develop the needed standardized files (TaskData.XML and Device Description Object Pool), the capabilities needed of the implement ECU program, the validation of communication between the implement ECU with the TC (management tractor ECU) and was prove that the information systematized has facilitated and provided the communication. It is expect that this work may open opportunities for the ISO 11783 standard can be better understood and enlarge the possibility of providing a great number of applications involving the concept of AP in Brazil.
462

Protocolo ISO 11783: procedimentos para comunicação serial de dados do controlador de tarefa / ISO 11783 protocol: procedures for serial data communication with the task controller

Pereira, Robson Rogério Dutra 29 January 2009 (has links)
O recente crescimento da utilização de tecnologias de automação e eletrônica embarcada em máquinas e implementos agrícolas tem estabelecido uma nova prática na área agrícola. Estas novas práticas relacionadas com a agricultura de precisão (AP) têm demandado a utilização de sensores e redes de comunicação embarcadas para aquisição de dados e controle dos dispositivos em campo. A incompatibilidade entre equipamentos e formatos de dados tornou-se um grande obstáculo. A tendência global é de uso de sistemas padronizados de acordo com a norma ISO 11783 (também conhecida como ISOBUS) nos dispositivos, ou Electronic Control Unit (ECU), utilizados na produção agrícola. No Brasil, essas ferramentas ainda não são largamente aplicadas. O objetivo deste trabalho é sistematizar as informações necessárias dos procedimentos para comunicação de uma ECU do implemento com a ECU de trator de gerenciamento. Focou-se no desenvolvimento dos arquivos padrões necessários e no programa da ECU do implemento, e testes de validação da comunicação dos dispositivos via rede ISO 11873. Estabeleceu-se a relação entre as informações sistematizadas e os dispositivos embarcados em máquinas agrícolas. Os dispositivos embarcados consistem em cinco ECUs interconectadas pela rede ISO 11783. Quatro ECUS estão localizados no tractor: ECU do GPS, Controlador de Tarefas (TC), Terminal Virtual (VT) e ECU do Trator (TECU). A ECU do GPS é responsável pela recepção do sinal do Differencial Global Position System (DGPS) e disponibilização na rede ISO 11783. O TC é responsável pelo gerenciamento da aplicação do mapa de prescrição e pelo controle do implemento. O VT é responsável por monitorar e disponibilizar uma interface gráfica com o operador da máquina. O TECU disponibiliza a velocidade do trator obtida por um sensor de radar. A quinta ECU está localizado no implemento, definido como Working Set Master (WSM), que é responsável por interpretar os comandos das ECUs do trator e integrar o dispositivo mecânico-hidráulico para realização de uma aplicação agrícola. Este trabalho mostrou os requisitos necessários para o desenvolvimento dos arquivos necessários (TaskData.XML e o Device Description Object Pool), as capacidades necessárias para o programa da ECU do Implemento, a validação da comunicação da ECU do Implemento com o TC (ECU do trator de gerenciamento) e comprovou que as informações sistematizadas facilitaram e proporcionaram a implementação de um sistema ISO 11783. Espera-se, que este trabalho possa abrir oportunidades para que a norma ISO 11783 possa ser melhor entendida e ampliar a possibilidade de disponibilizar um número maior de aplicações que envolvem o conceito de AP no Brasil. / The recent growth of automation technology and embedded electronic in agricultural machinery has established a new practice in agriculture. These new practices related to precision agriculture (PA) have demanded the use of sensors and communications embedded networks for data acquisition and control devices in the farm field. The incompatibility between hardware, software and data formats has become a major obstacle. The global trend is to use standardized systems in accordance with ISO 11783 (also known as ISOBUS) in the devices, or Electronic Control Units (ECU), used in agricultural production. In Brazil, these tools are not yet implemented. The purpose of this work is to systemize the information necessary of the procedures for communication among the implement ECU with management tractor ECU. This work focuses standardized files format, the program of the implement ECU and the validation tests of the devices communication via ISO 11873 network. It was established the relation among the systematized information and embedded devices on agricultural machinery. The embedded devices consist in five ECUs connected in the ISO 11783 network. Four ECUs are located in the tractor: GPS ECU, Task Controller (TC), Virtual Terminal (VT) and Tractor ECU (TECU). The GPS ECU is responsible to the Differential Global Positioning System (DGPS) positioning. The TC is responsible to manage the prescription map and to control the implement. The VT is responsible monitor the application. The TECU disposes tractor velocity of a radar sensor. The fifth device located in the implement is Working Set Master (WSM), which is responsible to interpret the commands from the tractors ECUs and integrate the mechanical-hidraulical device instruction for agricultural operation. It was presented how to develop the needed standardized files (TaskData.XML and Device Description Object Pool), the capabilities needed of the implement ECU program, the validation of communication between the implement ECU with the TC (management tractor ECU) and was prove that the information systematized has facilitated and provided the communication. It is expect that this work may open opportunities for the ISO 11783 standard can be better understood and enlarge the possibility of providing a great number of applications involving the concept of AP in Brazil.
463

Siamese Network with Dynamic Contrastive Loss for Semantic Segmentation of Agricultural Lands

Pendotagaya, Srinivas 07 1900 (has links)
This research delves into the application of semantic segmentation in precision agriculture, specifically targeting the automated identification and classification of various irrigation system types within agricultural landscapes using high-resolution aerial imagery. With irrigated agriculture occupying a substantial portion of US land and constituting a major freshwater user, the study's background highlights the critical need for precise water-use estimates in the face of evolving environmental challenges, the study utilizes advanced computer vision for optimal system identification. The outcomes contribute to effective water management, sustainable resource utilization, and informed decision-making for farmers and policymakers, with broader implications for environmental monitoring and land-use planning. In this geospatial evaluation research, we tackle the challenge of intraclass variability and a limited dataset. The research problem centers around optimizing the accuracy in geospatial analyses, particularly when confronted with intricate intraclass variations and constraints posed by a limited dataset. Introducing a novel approach termed "dynamic contrastive learning," this research refines the existing contrastive learning framework. Tailored modifications aim to improve the model's accuracy in classifying and segmenting geographic features accurately. Various deep learning models, including EfficientNetV2L, EfficientNetB7, ConvNeXtXLarge, ResNet-50, and ResNet-101, serve as backbones to assess their performance in the geospatial context. The data used for evaluation consists of high-resolution aerial imagery from the National Agriculture Imagery Program (NAIP) captured in 2015. It includes four bands (red, green, blue, and near-infrared) with a 1-meter ground sampling distance. The dataset covers diverse landscapes in Lonoke County, USA, and is annotated for various irrigation system types. The dataset encompasses diverse geographic features, including urban, agricultural, and natural landscapes, providing a representative and challenging scenario for model assessment. The experimental results underscore the efficacy of the modified contrastive learning approach in mitigating intraclass variability and improving performance metrics. The proposed method achieves an average accuracy of 96.7%, a BER of 0.05, and an mIoU of 88.4%, surpassing the capabilities of existing contrastive learning methods. This research contributes a valuable solution to the specific challenges posed by intraclass variability and limited datasets in the realm of geospatial feature classification. Furthermore, the investigation extends to prominent deep learning architectures such as Segformer, Swin Transformer, Convexnext, and Convolution Vision Transformer, shedding light on their impact on geospatial image analysis. ConvNeXtXLarge emerges as a robust backbone, demonstrating remarkable accuracy (96.02%), minimal BER (0.06), and a high MIOU (85.99%).
464

Erfassung, Analyse und Modellierung des Wurzelwachstums von Weizen (Triticum aestivum L.) unter Berücksichtigung der räumlichen Heterogenität der Pedosphäre

Schulte-Eickholt, Anna 02 August 2010 (has links)
Das Wurzelwachstum von Winterweizen wurde erfasst und modelliert, um teilflächenspezifisches Boden- und Düngemanagement zu verbessern. Die Variation von Wurzellängendichten im Feld wurde über zwei Vegetationsperioden hinweg an zwei unterschiedlichen Standorten in Ostdeutschland untersucht. Zur Auswertungserleichterung der hohen Anzahl an Wurzelproben, wurde eine halbautomatische Methode zur Bildanalyse von Wurzeln entwickelt. Der Einfluss von Änderungen bezüglich Bodenwasserstatus und Bodendichte bzw. Durchdringungswiderstand auf das Wurzelwachstum wurde untersucht. Die erhobenen Felddaten dienten gleichzeitig dazu, die Bodenwasser- und Wurzelwachstumsberechnung des Modells CERES-Wheat zu validieren. Das Modell simulierte die unterschiedlichen Bodeneigenschaften sowie die Wurzellängendichten und Bodenwassergehalte nur unzureichend. Der Effekt von Änderungen der Niederschlagsmengen auf die Simulationen von Wurzellängendichten und Bodenwassergehalten wurde anhand einer Unsicherheitsanalyse getestet und war extrem gering. Des Weiteren wurde eine Methode für praktische Zwecke entwickelt, mit der die Generierung von räumlich hoch aufgelösten Bodeninformationen unter Verwendung limitierter Eingangsdaten möglich ist. Die Modellkalkulationen basieren auf der Dempster-Shafer-Theorie. Anhand von multitemporal und multimodal erfassten Bodenleitfähigkeitsdaten, die Eingangsdaten für den Modellansatz sind, wurden Bodentypen und Texturklassen bestimmt. Das Modell generiert eine digitale Bodenkarte, die flächenhafte Informationen über Bodentypen und Bodeneigenschaften enthält. Die Validation der Bodenkarte mit zusätzlich erhobenen Bodeninformationen ergab gute bis sehr gute Ergebnisse. / Winter wheat root growth was measured and modelled to improve site-specific soil and fertilizer management in commercial wheat fields. Field variations in root length densities were analysed at two contrasting sites in East-Germany during two vegetation seasons. A semi-automated root analysing method was developed to facilitate analyses of large numbers of samples. Influences of variations in soil water states, bulk densities and penetration resistances on spatial distributions of roots were quantified. Differences in soil characteristics were large between the two sites and affected root growth considerably. The same field data was used for validating the soil moisture and root growth calculations of the widely applied growth model CERES-Wheat. Simulations of root length densities, soil physical properties and soil water contents were inadequate. The effects of changes of rainfall variabilities on simulated root length densities and soil water contents were tested by uncertainty analysis but were negligible low. A methodology for generating soil information for practical management purposes at a high degree of spatial resolution using limited input information was developed. The corresponding model calculations were carried out based on the Dempster and Shafer theorem. Soil types and texture classes were determined with multimodally and multitemporally captured data of soil electrical conductivities which are required input data of the new model approach. The model generates a digital map with extensive information of spatial variations in soil properties. The validation of the generated soil map with soil data from independent measurements yielded close correlation between measured and calculated values.
465

Identificação de possíveis áreas afetadas por sais no Perímetro Irrigado de São Gonçalo por meio do sensoriamento remoto. / Identification of possible areas affected by salts in the Irrigated Perimeter of São Gonçalo through remote sensing

OLIVEIRA, Woslley Sidney Nogueira de. 10 May 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-10T18:06:15Z No. of bitstreams: 1 WOSLLEY SIDNEY NOGUEIRA DE OLIVEIRA - DISSERTAÇÃO PPGSA ACADÊMICO 2018..pdf: 7059892 bytes, checksum: 1ab51771320e5bbd6c88d3c01b4b7aeb (MD5) / Made available in DSpace on 2018-05-10T18:06:15Z (GMT). No. of bitstreams: 1 WOSLLEY SIDNEY NOGUEIRA DE OLIVEIRA - DISSERTAÇÃO PPGSA ACADÊMICO 2018..pdf: 7059892 bytes, checksum: 1ab51771320e5bbd6c88d3c01b4b7aeb (MD5) Previous issue date: 2018-02-22 / Os perímetros irrigados implantados no Estado da Paraíba são considerados uma alternativa econômica bastante rentável, promove a geração de empregos e aumenta a disponibilidade de alimentos. Devido ao manejo inadequado do solo e da água, isso têm causado perdas na qualidade do solo desses perímetros, degradando-os principalmente por salinização. O sensoriamento remoto é uma alternativa tecnológica de baixo custo, boa frequência temporal e possui a capacidade de mapear áreas em processo de desertificação. Essa pesquisa têm por objetivo identificar possíveis áreas afetadas por sais no Perímetro Irrigado de São Gonçalo (PISG), Sousa- PB, por meio de técnicas de sensoriamento remoto. Para esse estudo foi utilizado imagens do satélite LANDSAT 8/OLI (média resolução espacial), órbita 216 / ponto 65 da data de 23/11/2016; imagem do software Google Earth Pro® da data de 29/02/2016 para servir como imagem auxiliar e registros fotográficos das áreas in loco. Realizou-se a técnica de classificação supervisionada, utilizando o SCP (semi- automatic plugin) no software QGIS (Quantum Gis). A aferição da qualidade da classificação se deu por meio da validação cruzada, utilizando de parâmetros estatísticos como a exatidão do produtor (EP), exatidão do usuário (EU), exatidão global (EG) e índice Kappa. A classe área supostamente salinizada (ASS) apresentou EP e EU de 89.15% e 88.88%, respectivamente. O índice Kappa resultou em um valor de 0.8684, a classe ASS foi classificada como sendo de qualidade excelente. A qualidade geral da classificação é avaliada tanto pela EG que apresentou um valor de 0.9350 como pelo índice Kappa geral com valor de 0.9252, sendo valores que representam uma classificação de qualidade excelente. A classe ASS apresentou os maiores valores mínimos e máximos de fator de refletância em todas as bandas da imagem, destacando a banda 6 de valores 0.47 e 0.67, respectivamente. O valor da área classificada como sendo da classe ASS foi de 1736.75 hectares, 31% da área total do PISG. As imagens analisadas possibilitaram discriminar áreas salinizadas e não salinizadas mediante as diferenças de tonalidade e de refletância. As imagens analisadas com o plugin SCP possibilitaram a realização de um mapa de classificação supervisionada, indicando a variabilidade espacial das áreas propícias ao processo de salinização. No entanto, recomenda- se a análise dos parâmetros físicos e químicos do solo dessas áreas para o aumento da confiabilidade na qualidade desse tipo de mapeamento. / The irrigated perimeters implemented in the State of Paraiba are considered a costeffective alternative quite profitable, promotes the generation of jobs and increases the availability of food. Due to inadequate management of soil and water, that have caused losses in soil quality of these perimeters, degrading them mainly by salinization. Remote sensing is an alternative low-cost technology, good temporal and frequency has the ability to map areas in process of desertification. This research aim to identify potential areas affected by salts in the irrigated perimeter of São Gonçalo (PISG), Sousa-PB, through remote sensing techniques. For this study we used LANDSAT satellite images 8/OLI (average spatial resolution), 216/orbit point 65 of 07/11/2016 date; image of the Google Earth Pro software® from date of 29/02/2016 to serve as auxiliary image and photographic records of the areas on the spot. The supervised classification technique, using the SCP (semi-automatic plugin) in software QGIS (Quantum Gis). The measurement of the quality of the classification took place by means of cross-validation, using statistical parameters such as the accuracy of the producer (EP), accuracy of the user (EU), global (EG) accuracy and Kappa index. The area class supposedly salinated (.ASS) presented EP and I of 89.15% and 88.88%, respectively. The Kappa index resulted in a value of .ASS class 0.8684 was classified as being of excellent quality. The overall quality of the classification is assessed both by EG who presented a 0.9350 value as the Kappa index 0.9252 valued General, being values that represent a rating of excellent quality. The class ASS presented the largest minimum and maximum values of reflectance factor in all the bands in the image, highlighting the band 6 0.47 values and 0.67, respectively. The value of the area classified as being of .ASS class was 1736.75 acres, 31% of the total area of the PISG. The images reviewed discriminate salinated areas and not allowed saline through the variations of shade and reflectance. The images analyzed with the SCP plugin enabled the creation of a map of supervised classification, indicating the spatial variability of the areas prone to salinization process. However, it is recommended that the analysis of the physical and chemical soil parameters of these areas for increased reliability in the quality of this type of mapping.
466

A systematics for interpreting past structures with possible cosmic references in Sub-Saharan Africa

Wade, Richard Peter 05 May 2009 (has links)
This thesis presents a method of identifying astronomical expressionsinherent within the spatial geography, cultural landscapes, and layouts of structures with a view to implementing the systematics in an African context. In determining astronomical codes of the southern African pre - early farmer and metalworking archaeological sites - this review deals with oral tradition, rituals, formative calendars, fertility, meteorites, eclipses, bio-diversity, sustainable agriculture, rainmaking and the general star lore. Conclusions are drawn from the hypothesis that certain structures functioned as astronomical expressions by use of monoliths and other configurations, with specific examples of how these possibilities were drawn from aspects within the Mapungubwe/Zimbabwe Cultural Complex and the preceding riverine cultural formations. / Dissertation (MSc(Applied Science))--University of Pretoria, 2009. / Architecture / unrestricted

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