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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

Systém zabezpečení včelích úlů před nepovolenou manipulací / Beehive security system against unauthorized manipulation

Milota, Martin January 2021 (has links)
This master thesis deals with the design of beehive security system against unauthorized manipulation. The system uses LoRaWAN wireless communication technology for data transmission. The device records the movement of the beehive using an accelerometer and then locates the beehive using a GPS module. The low-energy system works via a battery-powered ESP32 microcontroller and is located on a beehive. The battery is charged using a solar panel. The system can be modularly expanded with additional sensors to monitor the condition of the bees. The device has been tested in practice, where it has been confirmed that it meets the required properties for securing beehives.
2

Battery Powered Adaptive Grow Light System Aiming at Minimizing Cost and Environmental Impact from Electricity Use

Nowell, Thomas, Kollin, Viktor January 2022 (has links)
With increasing popularity of indoor farming, more and more home growers are faced with sub-optimal lighting conditions in northern countries or poorly lit windows. We have designed and built a proof-of-concept system capable of reducing electricity cost and CO2 footprint of the electricity used for consumer grade grow lights without adversely impacting the grow cycle of the plant. Our system provides optimal grow light conditions for a given plant while using forecasts and live grid data from the ENTSO-E transparency platform to automatically use or store electricity during low-cost hours and avoid using grid electricity during high-cost hours, but can also be configured to prioritize electricity use when the available grid power’s carbon intensity is low. The system, consisting of a server and an embedded control unit, was designed and implemented according to Nunamaker and Chen’s five-step iterative systems development research method and later evaluated by simulating the system for 14 days using real world sunlight and grid data. The results of the simulation show a significant reduction in both spending and carbon emissions related to electricity use, with figures of 73% and 28%, respectively. However, when accounting for life-cycle cost and emissions from the battery, the prototype in its current configuration is neither profitable nor a net positive for the environment. With changes to battery type and taking advantage of economies of scale, a future version could be economically viable, but to be environmentally sustainable, further advances in eco-friendly battery production are needed.
3

Modeling, Simulation & Implementation of Li-ion Battery Powered Electric and Plug-in Hybrid Vehicles

Mantravadi, Siva Rama Prasanna 15 August 2011 (has links)
No description available.
4

Design and development of energy-efficient transmission for wireless IoT modules / Conception et développement d'une transmission écoénergétique pour les modules IoT sans fil

Shakya, Nikesh Man 06 February 2019 (has links)
L'Internet des objets (IoT) devrait interconnecter plus de 50 milliards d’objet d'ici à 2020. Avec l'IoT, une variété d’objets de différentes industries seront interconnectés à travers Internet. Avec un accent sur la gestion et le stockage des ressources énergétique et l'eau. L'IoT permet d’enrichir les services fournis par les distributeurs d’énergie à travers les smart-grid au-delà de la distribution, de l'automatisation et du contrôle. Les systèmes de gestion pour la domotique et les bâtiments intelligents aideront les consommateurs à surveiller et à ajuster leur consommation. Les compteurs intelligents fournissent ainsi un ensemble d’information permettant aux fournisseurs d’énergie de mettre en place des services plus intelligents pour l'ensemble de la chaîne de production d'énergie. L'objectif principal de ce projet de recherche doctorale est de développer des modules de communication très basse consommation. La consommation énergétique étant la plus grande contrainte pour les applications de compteurs intelligents. Les objets connectés alimentés par batterie tels que les capteurs et compteurs de gaz et d'eau sont concernés directement par la consommation en énergie de leur module de communication. Aujourd'hui, la plupart des solutions sans fil embarquées conçues pour capteurs alimentés ne sont pas compatible avec la pile protocolaire IPv6 afin d’économiser la consommation énergétique. Élaborer des technologies sans fil de l'IoT pour atteindre les objectifs de consommation d'énergie va démocratiser l’utilisation de ces technologies et aider les solutions de l’IoT à trouver leur place sur le marché. Ce doctorat débutera par: 1) Un état de l'art permettant d'examiner les solutions actuelles développées pour les réseaux de capteurs et des protocoles conçus pour les appareils alimentés par batterie. 2) Dans un deuxième temps en examinant les solutions Itron pour IPv6 réseau maillé. 3) La troisième phase sera la proposition et la conception d'une solution à faible consommation pour les modules sans fil et l'internet des objets. 4) Et enfin l’expérimentation et la validation des solutions proposées sur des plateformes d’expérimentations / The Internet of Things (IoT) is expected to grow to 50 billion connected devices by 2020. Within the IoT, devices across a variety of industries will be interconnected through the Internet and peer-to-peer connections as well as closed networks like those used in the smart grid infrastructure. With the global focus on energy and water management and conservation, the IoT will extend the connected benefits of the smart grid beyond the distribution, automation and monitoring being done by utility providers. Management systems for in-home and in-building use will help consumers monitor their own usage and adjust behaviors. These systems will eventually regulate automatically by operating during off-peak energy hours and connect to sensors to monitor occupancy, lighting conditions, and more. But it all starts with a smarter and more connected grid. Smart metering provides a base around which utilities can build up smarter advanced services for the whole chain of energy generation, transmission and distribution. The main objective of this doctoral research project is to come up with the IoT communication modules with very low consumption characteristics. The energy consumption is the most challenging issue for smart home and smart metering applications. The battery powered devices such as sensors and gas and water meters are concerned directly with the consumption of their communication module. Today most of the embedded wireless solutions designed for sensors and battery powered devices do not embed IPv6 stack in the communication module to have a basic hardware with low consumption. Elaborating IoT wireless technologies to achieve the tough energy consumption objectives imposed to them will boost up the spread of these technologies and help IoT to find its place in the market fast. This PhD program will start with: First) a state of the art and reviewing the current solutions developed for sensor networks and protocols designed for battery powered devices. Second) it continues by reviewing Itron solutions for IPv6 meshed network. Third) Design of a low consumption solution for IoT wireless modules and) finally test and experimentation on platform
5

IoT systém pro zahrádkáře / IoT system for gardening

Mlčák, Petr January 2021 (has links)
The thesis deals with the design and creation of a weather station suitable for gardeners. The created device is able to measure temperature, pressure, humidity, amount of precipitation, wind speed and direction, UV index and also temperature and soil moisture at several depths. The weather station is powered by a battery with auxiliary charging from a photovoltaic panel. The thesis is divided into several parts. The theoretical part describes the individual physical principles of measurement of the considered physical quantities. Subsequently, a comparison of available sensors is made and then a final selection is made. The third part deals with the design and implementation of the hardware circuitry including the creation of the PCB. In this section, the holders of each sensor are also designed for printing on a 3D printer, which are then printed. The fourth section deals with software design issues, which is described in more detail. Finally, the whole weather station is assembled, wired and the functionality of all components is verified by sending the measured data to Thingspeak.
6

Akumulátorová sekačka na trávu / Battery supplied lawn mower

Picmaus, Jan January 2021 (has links)
The thesis deals with a concept of turning a conventional petrol powered lawn mower to a battery powered solution which is powered by lithium cells. A division to three chapters, comparison, mechanical and electrical, provides fluency of the whole design and further realization. The arrangement of chapters is performed so that the continuity of the thesis is maintained. Calculations of parameters of every motor and transmission with choosing particular devices are just a part of much interesting information which can be found in this thesis. All new components have full documentation except those which were changed during manufacturing. The electrical part explains every part of the schematics in detail. The realization contains difference between preliminary design and further production, manufacturing of the PCB and powering up the motor drives. The last part of the thesis contains temperature measurements of the device at no load.
7

Bezdrátové pohotovostní přivolání ošetřovatelské služby / Wireless Nurse Care Calling

Bubník, Karel January 2010 (has links)
This work describes the design, construction a performance of such a complete wireless pager suitable for health care centers, rest homes, home application, for example for calling an attendant. This appliance is designed to be easy to attendance. A wireless transceiver is simplified and is attended only by one button. A wireless receiver also doesn't require a complicated manipulation. The aim is to create pager, which will be an useful assistant thanks to its price and simple construction.
8

MULTI-OBJECTIVE DESIGN OF DYNAMIC WIRELESS CHARGING SYSTEMS FOR HEAVY – DUTY VEHICLES

Akhil Prasad (9739226) 15 December 2020 (has links)
<p>Presently, internal combustion engines provide power to move the majority of vehicles on the roadway. While battery-powered electric vehicles provide an alternative, their widespread acceptance is hindered by range anxiety and longer charging/refueling times. Dynamic wireless power transfer (DWPT) has been proposed as a means to reduce both range anxiety and charging/refueling times. In DWPT, power is provided to a vehicle in motion using electromagnetic fields transmitted by a transmitter embedded within the roadway to a receiver at the underside of the vehicle. For commercial vehicles, DWPT often requires transferring hundreds of kW through a relatively large airgap (> 20 cm). This requires a high-power DC-AC converter at the transmitting end and a DC-AC converter within the vehicle. </p> In this research, a focus is on the development of models that can be used to support the design of DWPT systems. These include finite element-based models of the transmitter/receiver that are used to predict power transfer, coil loss, and core loss in DWPT systems. The transmitter/receiver models are coupled to behavioral models of power electronic converters to predict converter efficiency, mass, and volume based upon switching frequency, transmitter/receiver currents, and source voltage. To date, these models have been used to explore alternative designs for a DWPT intended to power Class 8-9 vehicles on IN interstates. Specifically, the models have been embedded within a genetic algorithm-based multi-objective optimization in which the objectives include minimizing system mass and minimizing loss. Several designs from the optimization are evaluated to consider practicality of the proposed designs.
9

Considerations and Development of a Ventilation on Demand System in Konsuln Mine

Gyamfi, Seth January 2020 (has links)
Ventilation on demand (VOD) concept has earned significant worldwide attention by several mining companies in recent years. It is a concept where airflow is provided only to areas that require ventilation. The implementation of the concept has resulted in significant savings in annual energy consumption and cost for several companies globally. The research presented in this thesis sought to present the VOD system as an alternative solution and strategy to improve the ventilation system of Konsuln mine. The system is expected to cope with a planned increase in production rate and meet requirements in the new Swedish Occupational Health &amp; Safety (OH&amp;S) regulations, Arbetsmiljöverkets förtfattningssamling (AFS) 2018:1, which is based on the EU directive 2017/164 where Threshold Limit Value (TLV) for gases have been significantly reduced and provide safe work environment for workers in the mine. The thesis work started with planning and execution of a PQ (Pressure – Quantity) survey to calibrate the existing ventilation model of Konsuln mine. This was to ensure that the model is reasonably accurate to give reliable simulation predictions of the performance of Konsuln ventilation system in its current state and for the future. The good correlation between the modelled and underground measured values validated the model for further ventilation planning. The study further investigated and analyzed the current and future ventilation demand of LKAB test mine, Konsuln, to design a VOD system for its operations.The work outlined three main VOD design scenarios I, II, and III based on the proposed production plan, schedule, and the mining process that present the underground working conditions on the three main levels (436, 486 and 536) of Konsuln mine. Diesel, battery-powered, heat, and blast simulations were carried out for all the scenarios in the calibrated ventilation model using VentSim Design simulation software. The model was again used to estimate the annual ventilation power cost for the VOD scenarios to highlight the benefit and cost savings advantage under the VOD design system to deliver enough airflow quantity compared to the conventional system of ventilation. Simulation results showed that about 15.6% – 49.1% and 76.4% - 86.7% of significant cost savings will be achieved for diesel and battery-powered machineries respectively, while still supplying the needed amount of air to working areas to keep contaminants below their Threshold Limit Value -Time Weighted Average (TLV-TWA) and provide a good working environment. For additional benefits and savings of the Ventilation on Demand (VOD) system implementation, some considerations for equipment, personnel positioning and identification, monitoring system, and stations have also been discussed in this work.  These include; (i) Utilization of LKAB’s database system, Giron, in addition to mounting tags with unique IDs on machineries, to track the route of LHDs and trucks to deal with the challenge of airflow supply shortfall associated with auxiliary fans adjustment to affect target locations. (ii) Installation of temperature sensors, flow meters, gases and Diesel Particulate Matter (DPM) monitoring systems at specific, appropriate, and optimal locations in the mine for efficient implementation of the VOD system strategy. The heat simulations for both diesel and battery-powered machineries were carried out for the month of July when the highest temperatures in Kiruna are often recorded for the summer. They predicted the highest temperatures in working areas to be well below the limit used in Australia, 28°C Wet Bulb (WB). Four scenarios A, B, C and D were also considered for blast clearance time simulation using both the ramp and exhaust shaft. The blast simulation results indicated that the time to dilute and clear blast fumes through the exhaust shaft saves some clearance time compared to exhaustion through the ramp, although the shaft exhaustion will require additional financial commitment to purchase and install exhaust fans on each of the three main levels of the mine. Nevertheless, major ventilation work and practices such as removal of regulator in front of primary fans, additional radon measurement, and good auxiliary ventilation practices have been recommended to improve and actualize the benefits outlined in this work.

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