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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

Mikrotalasni senzori vlažnosti zemljišta zasnovani na komponentama sa distribuiranim parametrima / Microwave soil moisture sensors based on distributed elements

Kitić Goran 04 October 2016 (has links)
<p>Senzori vlažnosti zemljišta su od ključnog značaja za sisteme za navodnjavanje kojima je moguće uvećati prinose u proseku za 79%. U okviru ove disertacije razvijena su dva senzorska rešenja za merenje vlažnosti zemljišta. Prvi senzor je namenjen određivanju vlažnosti uzoraka zemljišta u neporemećenom stanju. Rešenje je nastalo nadogradnjom standardne opreme za uzorkovanje zemljišta. Za pomenuti senzor konstruisana je kalibraciona kriva kojom je moguće odrediti vlažnost zemljišta sa relativnom greškom ne većom od 2.5%. Drugo senzorsko rešenje je fabrikovano u LTCC tehnologiji, malih je dimenzija i namenjeno je primeni na terenu. Glavna prednost ovog senzora je da na njega ne utiče provodnost zemljišta koja je usko povezana sa tipom zemljišta. Predloženi senzor je testiran na dva uzorka zemljišta različitog hemijskog sastava. Rezultati merenja su pokazali da tip zemljišta nema uticaj na odziv senzora. Ostvarena relativna greška u odnosu na pun merni opseg iznosi 5.36%.</p> / <p>Soil moisture sensors are of great importance for the irrigation systems that<br />are able to increase the yiel on avarage of 79%. Within this thesis two sensor<br />solutions have been developed. The first sensor, which is intended for<br />laboratory use, has been designed by upgrading existing sampling<br />equipment. The constructed calibration curve for this type of sensor that can<br />be used for soil mositure determination with relative error not larger than<br />2.5% with respect to full scale output. The second sensor solution is<br />designed to be used in the field. It is fabricated in LTCC technology and it is<br />charaterized by small overall dimensions. The main advantage of this sensor<br />is that it is immune to the soil electrical conductivity which is closely related to<br />the soil type. Proposed sensor is tested on two soil sample of different<br />chemical composition and the results have shown that the type of soil does<br />not influence the sensor response. The relative error with the respect of full<br />scale output was only 5.36 %.</p>
2

Sistema de supervisão e controle de irrigação utilizando técnicas de inteligência artificial

Fontes, Ivo Reis [UNESP] 18 December 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-12-18Bitstream added on 2014-06-13T19:41:53Z : No. of bitstreams: 1 fontes_ir_dr_botfca.pdf: 6105136 bytes, checksum: 23e89a651c99005b7465ec2d3aae3e9b (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente trabalho teve como objetivo a configuração de um sistema de supervisão e controle de irrigação utilizando técnicas de inteligência artificial. De acordo com metodologia adotada, o seu desenvolvimento foi realizado em três fases distintas. Inicialmente foram construídos os seguintes módulos de hardware: Unidade de Sensores, Unidade Concentradora de Dados e Sensor de Umidade do Solo do tipo Capacitivo. Em seguida foi criada uma aplicação através do programa de supervisão e controle do tipo SCADA, Elipse PRO, dedicada à supervisão e controle de uma casa de vegetação. Na fase final foram coletados os dados necessários para o treinamento de uma rede neural artificial que é parte integrante do sensor de umidade de solo do tipo capacitivo. Os resultados obtidos através de um conjunto de teste de medidas demonstraram que o sensor capacitivo apresenta comportamento e desempenho similares ao do sensor de do tipo TDR, o que permite concluir que esta solução pode representar uma significativa contribuição, viabilizando a implantação de sistemas de supervisão e controle em processos de irrigação com uma relação custo/benefício em níveis aceitáveis. / The present work had as objective the configuration of a supervisory and control system for irrigation using artificial intelligence techniques. In agreement with adopted methodology, its development was accomplished in three different phases. Initially the following hardware modules were built: Sensors Unit, Data Concentrator Unit and a Capacitive type Soil Moisture Sensor. Soon afterwards an application was created through the supervisory and control program of the type SCADA, Ellipse PRO, dedicated to the supervision and control of a green house. In the final phase the necessary data were collected for the training of an artificial neural network that is integral part of the capacitive type soil moisture sensor. With the application developed in the Ellipse PRO a database was created for the training of the artificial neural network, containing a group of 2440 measures of soil moisture obtained through a capacitive type sensor and a TDR type sensor. The results obtained through a group of test of measures demonstrated that the capacitive sensor presents a similar behavior to the of the TDR type sensor, the one that allows conclude that this solution can represent a significant contribution, making possible the implantation of supervisory and control systems in irrigation processes with a cost/benefit relationship in acceptable levels.
3

Applicability of Soil Moisture Sensors in Determination of Infiltration Rate

K C, Milan January 2017 (has links)
No description available.
4

Sistema de supervisão e controle de irrigação utilizando técnicas de inteligência artificial /

Fontes, Ivo Reis. January 2003 (has links)
Orientador: José Angelo Cagnon / Banca: Nelson Miguel Teixeira / Banca: Edwin Avolio / Banca: Diógenes Pereira Gonzaga / Banca: André Torre Neto / Resumo: O presente trabalho teve como objetivo a configuração de um sistema de supervisão e controle de irrigação utilizando técnicas de inteligência artificial. De acordo com metodologia adotada, o seu desenvolvimento foi realizado em três fases distintas. Inicialmente foram construídos os seguintes módulos de hardware: Unidade de Sensores, Unidade Concentradora de Dados e Sensor de Umidade do Solo do tipo Capacitivo. Em seguida foi criada uma aplicação através do programa de supervisão e controle do tipo SCADA, Elipse PRO, dedicada à supervisão e controle de uma casa de vegetação. Na fase final foram coletados os dados necessários para o treinamento de uma rede neural artificial que é parte integrante do sensor de umidade de solo do tipo capacitivo. Os resultados obtidos através de um conjunto de teste de medidas demonstraram que o sensor capacitivo apresenta comportamento e desempenho similares ao do sensor de do tipo TDR, o que permite concluir que esta solução pode representar uma significativa contribuição, viabilizando a implantação de sistemas de supervisão e controle em processos de irrigação com uma relação custo/benefício em níveis aceitáveis. / Abstract: The present work had as objective the configuration of a supervisory and control system for irrigation using artificial intelligence techniques. In agreement with adopted methodology, its development was accomplished in three different phases. Initially the following hardware modules were built: Sensors Unit, Data Concentrator Unit and a Capacitive type Soil Moisture Sensor. Soon afterwards an application was created through the supervisory and control program of the type SCADA, Ellipse PRO, dedicated to the supervision and control of a green house. In the final phase the necessary data were collected for the training of an artificial neural network that is integral part of the capacitive type soil moisture sensor. With the application developed in the Ellipse PRO a database was created for the training of the artificial neural network, containing a group of 2440 measures of soil moisture obtained through a capacitive type sensor and a TDR type sensor. The results obtained through a group of test of measures demonstrated that the capacitive sensor presents a similar behavior to the of the TDR type sensor, the one that allows conclude that this solution can represent a significant contribution, making possible the implantation of supervisory and control systems in irrigation processes with a cost/benefit relationship in acceptable levels. / Doutor
5

Home Irrigation System : Using Internet Control

Girajala, Manikanta Satish Kumar, Vatsavayi, Sri Satyasai, Medavarapu, Veera Bhadra Prathith Kumar January 2021 (has links)
In this report an illustration of a Home Irrigation System Using Internet Control by Arduino is proposed. This automated system for irrigation identifies the moisture content present in soil and automatically toggles the switching off pump when the power is supplied. An appropriate usage of irrigation system is necessary and it is essential to maintain suitable water content and avoid shortage of water due to lack of rain and spontaneous use of water, to avoid wastage of water. Due to this reason, this home irrigation system can be used to monitor soil moisture. Which is very useful in all climatic conditions. This project aims at reducing excessive and uncontrolled water usage as well as maintaining moisture content of the soil to get healthy irrigation. Home Irrigation System can be used for saving time using monitoring device thus minimizing human effort. Overall, the project achieved its primary goal to avoid the wastage of water while maintaining the moisture content of the soil with less delay in the processing time.
6

[en] RAIN VS. MOISTURE RELATIONSHIP IN UNSATURATED SOILS / [pt] RELAÇÃO CHUVA VS. UMIDADE EM SOLOS NÃO SATURADOS

MARCELA STRONGYLIS 21 June 2021 (has links)
[pt] O propósito do trabalho é avaliar a viabilidade técnica do uso de sondas tipo TDR e tensiômetros no monitoramento de encostas não saturadas. Com tais instrumentos, objetiva-se monitorar a variação da sucção mátrica e da umidade no solo em períodos chuvosos, visando aperfeiçoar os sistemas de alerta usados em áreas de risco e, consequentemente, minimizar perdas materiais e humanas. Para as medições, foram instalados uma estação meteorológica (munida de um pluviômetro, um datalogger, uma placa solar e uma antena para a transmissão de dados via internet), quatro sensores de umidade tipo TDR e um tensiômetro de alta capacidade em uma encosta localizada a montante da Faculdade de Medicina de Petrópolis, cidade da região serrana do estado do Rio de Janeiro. Foram registrados cerca de três meses de dados das sondas tipo TDR e, por conta de uma pane elétrica, apenas treze dias de dados do tensiômetro. As sondas tipo TDR apresentaram tempos de resposta rápidos, com nítidos aumentos de umidade volumétrica com o início de um evento chuvoso. Elas também apresentaram sensibilidade adequada para serem utilizadas em sistemas de alerta, sendo capazes de registrar alterações de umidade volumétrica com pequenos volumes de chuva. As curvas características encontradas através de ensaios de papel filtro mostraram um bom paralelo entre as sucções medidas diretamente pelo tensiômetro e aquelas obtidas indiretamente pelas sondas tipo TDR, através da conversão das umidades volumétricas em sucção. / [en] The purpose of this work is to evaluate the technical feasibility of using TDR probes and tensiometers to monitor unsaturated slopes. The objective is to monitor with these instruments the variation of matric suction and soil moisture during rainy periods, aiming to improve the warning systems used in hazardous areas and, consequently, to minimize human and material loss. For the measurements, a meteorological station (equipped with a rain gauge, a datalogger, a solar panel and an antenna for data transmission via internet), four TDR-type humidity sensors and a high capacity tensiometer were installed in a slope located in the University of Medicine of Petrópolis, city of the mountainous region of the state of Rio de Janeiro. Approximately three months of data were collected from the TDR probes and only thirteen days of tensiometer data due to a power outage. TDR-type probes showed fast response time, with clear increases in volumetric humidity with the beginning of a rainfall event. They also showed adequate sensitivity to be used in warning systems, being able to register changes in volumetric humidity with small precipitation amounts. The characteristic curves found by the filter method showed a good correlation with the suctions measured directly by the tensiometer and those obtained indirectly by the TDR probes, by converting the volumetric humidity into suction.
7

Synthesis of Conceptual Designs for Sensors

Sarkar, Biplab January 2015 (has links) (PDF)
National Programme on Micro and Smart Materials and Systems (NPMASS) / A computer-aided technique is developed in this thesis to systematically generate concepts for sensors of a wide variety. A database of building blocks, based on physical laws and effects that capture the transduction rules underlying the working principles of sensors, has been developed to synthesize concepts. The proposed method uses the database to first create a concept-space graph and then selects concepts that correspond to paths in the graph. This is in contrast to and more efficient than existing methods, such as, compositional synthesis and graph-grammar synthesis, where solution paths are laid out first and then a concept-space graph is generated. The research also explores an approach for synthesis of concepts for closed-loop sensors, where a quantity is sensed indirectly after nullifying its effect by using negative feedback. These sensors use negative feedback to increase the dynamic range of operation without compromising the sensitivity and resolution. According to the literature, generation of un-interesting solutions is a major drawback of the building block-based synthesis approaches. In the proposed approach, this shortcoming is mitigated substantially by using some rules. For a number of the concepts generated, in the sensor problems attempted, we found that those concepts were already implemented in existing patents; thus emphasising the usefulness of the concepts produced. The synthesis approach proposed new, feasible sensor concepts, thereby indicating its potential as a stimulator for enhancing creativity of designers. Another important problem is to improve the robustness of designs. Robustness can be achieved by minimizing the side effects. Side effects are defined as unwanted effects that affect the intended working of the sensor. The research presents an algorithm that (a) predicts the potential side effects for the synthesized concepts of sensors; (b) aids in quantifying the magnitude of the side effects, thus helping the designer to predict the significant side effects; and (c) suggests ways to improve the robustness of the design.

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