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

Percepção socioambiental aplicada em instituição de ensino no âmbito da racionalização do uso da água a partir de aproveitamento de águas pluviais. / Environmental applied perception in institution of education in stream lining scope of use of water to water utilization from storm.

Suéllen da Silva Pereira 08 April 2014 (has links)
Devido à falta de água em algumas regiões, o tema aproveitamento de águas pluviais vem se desenvolvendo ultimamente. Fica evidente a importância de sensibilizar as pessoas para que ajam de modo responsável e com consciência. A escola é um espaço de sensibilidade e conscientização que pode educar os alunos junto ao meio escolar e à comunidade local sobre o meio ambiente. O objetivo do presente trabalho foi o de realizar no Instituto de Aplicação Fernando Rodrigues da Silveira (CAp-UERJ) uma pesquisa de percepção ambiental com os alunos do 2 e 5 ano dos anos iniciais do Ensino Fundamental, a partir da conscientização pautada na educação ambiental após instalado o sistema de captação de águas pluviais, desenvolvida no projeto de Manejo de Águas Pluviais - MAPLU aprovado pelo FINEP, cujo objetivo é o desenvolvimento de soluções urbanísticas e ambientalmente adequadas de manejo de águas pluviais. Foram realizadas as oficinas com cada grupo focal e aplicados questionários para avaliar os resultados gerados. As oficinas demonstraram um avanço no conhecimento, pois a partir de uma abordagem participativa, os alunos puderam expressar os seus interesses e conhecimentos. Para quantificar o consumo de água no Instituto, foram levantadas informações relativas aos usuários, medições de vazões e faturas de consumos de água disponibilizados pela Companhia Estadual de Águas e Esgoto - CEDAE. Por meio de entrevistas com amostras de população, verificou-se a frequência e o tempo médio de utilização dos aparelhos, bem como as principais atividades que consomem água. Estimou-se o consumo médio diário de água no CAp-UERJ em 13 L/dia por aluno. / The rainwater harvesting is a topic that has been developing in recent years. It is evident the importance of sensitizing people to act responsibly and conscientiously so. The school is an area of sensitivity and awareness that can educate students on the school environment and the local community about the environment. The objective of this study was to perform at the Institute of Application Fernando Rodrigues da Silveira (CAp-UERJ) a survey of environmental awareness with students of the 2nd and 5th year of the early years of elementary school, from the awareness guided environmental education after installation of the rainwater harvesting system, developed in the project stormwater management - MAPLU approved by FINEP, whose goal is the development of urban and environmentally sound solutions for stormwater management. Workshops with each focus group and applied questionnaires were conducted to evaluate the results generated, as the workshops results showed an improvement in knowledge, because, from a participatory approach, the students were able to express their interests and expertise. In order to quantify water consumption information was raised to users of the institution, measurements of flow and water consumption provided by the State Company for Water and Sewer bills - CEDAE. Through interviews with samples of the population, there was the frequency and the average time of use of equipment, as well as the main activities that consume water. We estimated the average daily water consumption in CAp-UERJ of 13 L / day per student.
12

Propuesta de implementación de un sistema complementario de abastecimiento de agua para uso sanitario proveniente de las aguas pluviales para cubrir los periodos de desabastecimiento del servicio de agua potable municipal SEMACEL, en la Institución Educativa Manuel de Piérola Castro del distrito de Celendín, departamento de Cajamarca / Proposal to implement a water supply system for sanitary use by using rainwater to compensate the periods of water shortages, from the municipal water service SEMACEL, at the Manuel de Pierola Castro educational institute located in Celendin, Cajamarca

Camones Villanueva, Jesús Ivan, Pahuara Silva, Angelo Martín 26 September 2021 (has links)
El Perú es uno de los países con mayores reservas de agua dulce en el mundo, ocupando el octavo lugar con una reserva de 1.89% de la disponibilidad mundial de agua dulce superficial. Sin embargo, a pesar de que existe abundante oferta del recurso hídrico, las brechas de acceso al agua son cada vez mayores. Los pueblos de la sierra peruana, no son ajenos a esta realidad, ya que, no cuentan con un eficiente abastecimiento de agua. Frente a esta problemática, el objetivo de la presente investigación es proponer un sistema de abastecimiento de agua en la I.E. Manuel de Piérola Castro, aprovechando la alta precipitación del distrito de Celendín. Para ello, se visitó la zona de estudio para determinar la oferta hídrica pluvial, estimar la demanda de consumo de agua de la I.E. Manuel de Piérola Castro y conocer la realidad problemática del distrito de Celendín. En el distrito de Celendín se registra precipitaciones medias de 6.28 mm por día, equivalentes a 5.1 litros de agua por metro cuadrado de cubierta de captación, lo cual, representa una alta capacidad de aprovechamiento de agua de lluvias para uso sanitario. A su vez, la instalación del sistema de aprovechamiento propuesto resulta factible debido al bajo costo que este representa. Finalmente, se evidencia beneficios de utilizar agua de lluvia, puesto que, significarían un ahorro en el pago a la entidad administradora de agua potable, se garantiza la continuidad del servicio de agua y se contribuye al manejo sostenible de los recursos hídricos. / Peru is a country that has one of the largest freshwater reserves in the world with it ranking 8th globally with a reserve of 1.89% of the total global amount of surface freshwater in the world. However, despite the abundance of this resource, the gaps in access to water are increasing. This situation is common among people living in the Peruvian highlands because they don’t have access to freshwater. The objective of this current investigation is to propose the use of a water supply system at I.E. Manuel de Piérola Castro that takes advantage of the high amount of rainfall in the district of Celendín. To do this, the study area was visited in order to determine the rainwater supply, estimate the demand for water consumption at I.E. Manuel de Piérola Castro and learn about the problematic reality that the Celendín district is going through. In the district of Celendín, 6.28 mm of average rainfall is recorded per day, which is equivalent to 5.1 liters of water in one square meter of catchment cover. This demonstrates the potential of using rainwater for sanitary use as the catchment cover of the Educational Institution Manuel de Piérola Castro covers more than 1300 square meters. Additionally, the installation of the proposed harvesting system is feasible due to its low cost. Finally, there are many benefits to using the proposed system such as savings on bills to the drinking water administration entity, guaranteed continuity of water, and sustainable water mismanagement. / Tesis
13

Système thermoélectrique pour la récupération d'énergie : modélisation électrique et continuité de service de la circuiterie électronique / Thermoelectric system for energy harvesting : electrical modeling and continuity of service of electronic circuit

Siouane, Saïma 06 December 2017 (has links)
La récupération d'énergie thermique basée sur les générateurs thermoélectriques (TEG) est utilisée dans de nombreuses applications telles que les dispositifs médicaux auto-alimentés. La sûreté de fonctionnement et la continuité de service de ces systèmes sont aujourd'hui des préoccupations majeures. Ainsi, toute défaillance au niveau d'un des interrupteurs commandables de la circuiterie électronique d'interface peut provoquer de graves dysfonctionnements du système. Tout défaut non détecté et non compensé peut mettre en danger l'ensemble du système et interrompt l'alimentation en énergie de la charge. Par conséquent, la mise en œuvre d'une compensation de défaut efficace et rapide est impérative afin d'assurer la continuité de service. Dans ces travaux de recherche, nous étudions la continuité de service d'une interface électronique pour TEG basée sur une conversion à deux étages Buck/Buck-Boost cascadés. Une modélisation électrique générique (modèle de Thévenin) du TEG sous différentes conditions de fonctionnement et prenant en compte l'ensemble des résistances thermiques de contact est tout d'abord présentée. Ensuite, une méthode de compensation de défaut de type circuit-ouvert au niveau de l'interrupteur commandable de l'un des deux convertisseurs DC-DC est également proposée. Nous présentons une topologie originale de convertisseur DC-DC à tolérance de pannes, sans redondance matérielle classique. Cette topologie permet d'assurer la continuité de service du système de récupération d'énergie en mode nominal. Les études théoriques ont été validées par simulation et par des tests expérimentaux / Thermal energy harevsting based on thermoelectric generators is used in many applications such as self-powered medical devices. The reliability and continuity of service of these systems are now major concerns. Furthermore, any failure in the controllable switch of the electronic interface circuitry can cause serious system malfunctions. Any undetected and uncompensated fault can endanger the entire system and interrupt the power supply to the load. Therefore, the implementation of an efficient and rapid fault compensation is imperative in order to ensure the continuity of service. In this research, we study the continuity of service of an electronic interface for TEG, based on a two-stage conversion cascaded Buck/Buck-Boost. A generic electrical modeling of the TEG model under different operating conditions and with taking into account all the thermal contact resistances is first presented. Next, an open-circuit fault compensation method of the controllable switch of one of the two DC-DC converters is also proposed. We present an original fault-tolerant DC-DC converter topology with no conventional hardware redundancy. This topology ensures the continuity of service of the energy recovery system in nominal mode. Theoretical studies were validated by simulation and experimental tests
14

Poly-Vinylidene Fluoride Based Vibration Spectrum Sensors and Energy Harvestors

Nyayapati, Mahidhar Ramesh January 2014 (has links) (PDF)
Mechanical vibrations in large structures such as buildings, bridges, dams and critical frequencies in large machinery generally have low frequencies (100Hz-1000Hz). To monitor large areas of such structures we need huge network of low cost, easily manufacturable, self-powered and stand-alone vibration spectrum sensors. The sensors should also consume very little power during their overall operation cycle and have moderately high frequency resoultion. The thesis provides mathematical analysis, design and development of stand-alone, low frequency vibration spectrum analyzer .A mechanically stretched polymer piezoelectric membrane, which has a fixed length and tension, can act as a single frequency detector due to its unique resonant frequency. Stretching multiple ribbons of diffferent lengths and tensions, a vibration spectrum analyzer, which gives the Fourier frequency components present in an arbitrary mechanical input vibration, can be designed. The thesis presents a detailed description of experiments to evaluate a low frequency vibration spectrum analyzer system that accepts an incoming input vibration and directly provides the spectrum as output. Polymer piezoelectric materials being easily manufacturable these sensors can be deployed in wide area sensor networks that monitor large structures. The thesis also shows design of a vibration energy harvesting system based on the concept of harvesting energy at low frequencies. The need for developing such an energy harvesting system arises from the necessity of making the vibration sensor, self-powered. Multiple experimental tests were performed before developing a prototype vibration energy harvesting circuit.
15

Utveckling av en solcellsförsörjningsenhet för IoT-sensornoder

Mulat, Adane Hailu January 2022 (has links)
Internet of Things (IoT) är en kraftfull plattform för att koppla den fysiska världen till den digitala. IoT och modern sensorteknik möjliggör många nya applikationer inom till exempel industriell övervakning, hälsovård,miljöövervakning, smarta städer, smarta transport och smartlivsstil. I många av dessa applikationer är sensornoder utplacerade i utomhusmiljöer, där de bör fungera under långa tidsperioder. IoT-noder lider av kapacitetbergränsade batterier vilket innebär att deras funktion beror på batteriets livslängd. En lösning kan vara att implementera ett energikördsystem till IoT-noder utomhus. Solenergi är den mest lättillgängliga och användbara energikällan utomhus.Denna energi skördas med hjälp av en solcell (PV-cell). Energin som genereras av solcellspaneler varierar beroende på solstrålningsintensitet och andra faktorer. Syftet med denna undersökning har varit att utveckla en solcellsförsörjningsenhet för IoT-noder utomhus. Detta görs genom att hämta energi från omgivningen (solenergi) och använda den i samband med en Power ManagementIntegrated Circuit (PMIC) och en energilagringsenhet kan livslängden för IoT-noder förlängas samtidigt som underhållskostnader minskas.I undersökningen användes en uppskattningsmetod för att uppskatta solcellens totala energiproduktion, vilket hjälper för att konfigurera en solcellspanel som kan leverera lämplig energi till energiskördsystemet och minska energiförlusten i systemet. En lämplig energi krävs för att PMIC:n ska fungera väl samt systemet ska driva IoT-noder. Denna undersökning har visat att solenergiskördsystemet som består av en självgjord mindre panel, en BQ25570 och en energilagringsenhet (antingen en superkondensator eller ett batteri) kan översvämningsmätaren drivas under sommaren för det första fallet och under hela året för det andra fallet. Om två i parallell KXOB25-01X8F-TR används i systemet i stället för den mindre panelen kan luftkvalitetmätaren drivas under sommaren medan om tre iparallell KXOB25-01X8F-TR används i stället kan noden drivas under hela året. Energiskördsystemet ger mer än 80% effektivitet. / The Internet of Things (IoT) is a powerful platform for connecting the physical world to the digital. IoT and modern sensor technology enable many new applications in domains such as industrial monitoring, health care, environmentalmonitoring, smart cities and so on. In many of these applications, sensor nodes are deployed in outdoorenvironments, where they should operate for long periods oftime. But IoT nodes suffer from capacity-limited batteries,which means that their function depends on the battery life. One solution may be to implement an energy harvestingsystem for IoT nodes outdoors. Solar energy is the most readily available and useful source of energy outdoors. This energy is harvested using a solar cell (PV cell). The energy generated by solar cell panels varies depending on the solar radiation intensity and other factors. The purpose of this study has been to develop a solar cell supply unit for outdoor IoT nodes. This is done by extracting energy from the environment (solar energy) and using it in conjunction with a Power Management Integrating Circuit (PMIC) and energy storage device, the lifespan of IoT nodes can be extended while reducing maintenance costs. The study used an estimation method to estimate solar cell total energy production, which helps to configure a solar cellpanel that can supply suitable energy to the energyharvesting system and reduce the energy loss in the system. A suitable energy is required for the PMIC to work well and the system to power IoT nodes.This study has shown that the solar energy harvesting system consisting of a self-made smaller panel, a BQ25570 and an energy storage unit (either a supercapacitor or a battery), the flood meter can be operated during the summer for the first case and throughout the year for the second case. If two inparallel KXOB25-01X8F-TR are used in the system instead of the smaller panel, the air quality meter can be operated in the lower summer, while if three in parallel KXOB25-01X8F-TR areused instead, the node can be operated throughout the year. The energy harvesting system provides more than 80% efficiency.
16

Thermal Snail : Design and Performance Evaluation of a Non-Electronic Autonomous Vehiclefor Harnessing Thermal Expansion of Volatile Fluid for Movement

Chen, Xin, Velin, Benjamin January 2024 (has links)
No description available.

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