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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.
511

Fotovoltaický on-grid systém s akumulací / Photovoltaic on-grid system with accumulation

Kijovský, František January 2012 (has links)
This thesis deals with processing the current issue of trends in on-grid photovoltaic system with accumulation. It examines the posibility of accumulation of photovoltaic systems, analyzing their strengths and weaknesses in the practical deployment. It compares the different storage technologies based on indicators of cycles, durability and price ranges. The practical part deals with the technical design of hybrid power system and then comparing with the standard on-grid system in technical and economical point of view.
512

Analysis of cyber security in smart grid systems

Masonganye, James January 2017 (has links)
Cyber security is a major concern due to global incidents of intrusion. The impact of the attacks on the electricity grid can be significant, resulting in the collapsing of the national economy. Electricity network is needed by banks, government security agencies, hospitals and telecommunication operators. The purpose of this research is to investigate the various types of cyber security threats, including ICT technologies required for safe operation of the smart grid to protect and mitigate the impact of cyber security. The modelling of cyber security using the Matlab/SimPowerSystem simulates the City of Tshwane power system. Eskom components used to produce energy, interconnect to the City of Tshwane power distribution substations and simulated using Simulink SimPowerSystem. / Dissertation (MEng)--University of Pretoria, 2017. / Electrical, Electronic and Computer Engineering / MEng / Unrestricted
513

Reconfiguration of Hamiltonian cycles and paths in grid graphs

Nishat, Rahnuma Islam 11 May 2020 (has links)
A grid graph is a finite embedded subgraph of the infinite integer grid. A solid grid graph is a grid graph without holes, i.e., each bounded face of the graph is a unit square. The reconfiguration problem for Hamiltonian cycle or path in a sold grid graph G asks the following question: given two Hamiltonian cycles (or paths) of G, can we transform one cycle (or path) to the other using some "operation" such that we get a Hamiltonian cycle (or path) of G in the intermediate steps (i.e., after each application of the operation)? In this thesis, we investigate reconfiguration problems for Hamiltonian cycles and paths in the context of two types of solid graphs: rectangular grid graphs, which have a rectangular outer boundary, and L- shaped grid graphs, which have a single reflex corner on the outer boundary, under three operations we define, flip, transpose and switch, that are local in the grid. Reconfiguration of Hamiltonian cycles and paths in embedded grid graphs has potential applications in path planning, robot navigation, minimizing turn costs in milling problems, minimizing angle costs in TSP, additive manufacturing and 3D printing, and in polymer science. In this thesis, we introduce a complexity measure called bend complexity for Hamiltonian paths and cycles in grid graphs, and using those measures we measure complexity of a grid graph G and give upper and lower bounds on the maximum bend complexity of an mxn grid graph. We define three local operations, flip, transpose and switch, where local means that the operations are applied on vertices that are close in the grid graph but may not be close on the path or cycle. We show that any Hamiltonian cycle or path can be reconfigured to any other Hamiltonian cycle or path in an mxn rectangular grid graph, where m <= 4, using O(|G|) flips and transposes, regardless of the bend complexities of the two cycles. We give algorithms to reconfigure 1-complex Hamiltonian cycles in a rectangular or L-shaped grid graph G using O(|G|) flips and transposes, where the intermediate steps are also 1-complex Hamiltonian cycles. Finally, we establish the structure of 1-complex Hamiltonian paths between diagonally opposite corners s and t of a rectangular grid graph, and then provide a strategy, based on work in progress, for designing an algorithm to reconfigure between any two 1-complex s, t Hamiltonian paths using switch operations. / Graduate
514

Grid Computing - Eine Einführung

Petersen, Karsten 30 September 2003 (has links)
Workshop Mensch-Computer-Vernetzung Eine Einführung in Geschichte und Ideen des Grid-Computing. Kurze Vorstellung des 'Globus-Toolkit'.
515

A Grid Middleware for Ontology Access

Hartung, Michael, Rahm, Erhard 01 February 2019 (has links)
Many advanced grid applications need access to ontologies represent-ing knowledge about a certain application domain. To deal with the high heterogeneity of available ontologies, we propose a general ser-vice-oriented middleware for making ontologies accessible to grid ap-plications. Our implementation is integrated in the German D-Grid in-frastructure and provides several applications a uniform access to biomedical ontologies such as Gene Ontology, NCI Thesaurus and several OBO ontologies.
516

Řízení spotřeby v chytrých energetických sítích / Demand Management in Smart Grids

Nesveda, František January 2019 (has links)
With the rapid adoption of electric vehicles and the rise of power generation from re- newable sources, intelligent management of power demand on a household level is gaining importance. Current algorithms used for that purpose have negative privacy implications and focus only on controlling the charging of electric vehicles while ignoring other ap- pliances. We describe a decentralized algorithm designed to control the power demand of different types of household appliances along with the charging of electric vehicles while preserving the privacy of the subscribers. We also present a smart grid simulator to evaluate the algorithm's effectiveness along with results of simulating a scale model of the power grid of the state of Texas. 1
517

Mottagargrupper : En webbapplikation med AG-Grid

Holmström, Emilia January 2022 (has links)
The project is about a GS1-verified input system Prevas GCM, which is a web service for suppliers to send article information to receivers. With the current system the suppliers need to select each receiver individually when sending information. The purpose with the project is to develop a system that let suppliers create receivers groups from receivers. The preparatory work consist of create prototypes in Adobe XD. Thereafter the web application produced in two steps. The project has mostly used the programming language JavaScript together with AG-Grid. In addition html and css have been used. The result was a almost launch-ready product with minor fixes left. / Projektet har handlat om GS1-verifierat inmatningssystemet Prevas GCM, som är en webbtjänst som låter leverantörer skicka ut artikelinformation till mottagare. Den nuvarande lösningen innebär att leverantörerna måste välja alla mottagare enskilt. Syftet med projektet blev att utveckla en webbapplikation som låter leverantörer skapa mottagargrupper av mottagare. Förarbetet bestod av att skapa prototyper i Adobe XD. Därefter har webbapplikation tagits fram i två steg. Projektet har huvudsakligen använt programmeringsspråket JavaScript ihop med AG-Grid. Utöver det har HTML och CSS används. Resultatet blev nästan en lanserings-klar produkt med mindre fix kvar.
518

Analysis and design of a parking place with vehicle-to-grid electricity buffering

Bueno Nuin, Tomás January 2022 (has links)
The transition to a zero emissions society has already begun. A big effort should be done in the energy area and as engineers we have the power and the responsibility of using all our knowledge to look for the best and optimal solutions to achieve it.   The aim of this project is to study the new technologies that are appearing in the field of electric cars vehicles as well as try to develop a way of integrating this into a project of a real long-term parking. The study will be focused on the use of the technologies known as V2X. This technology has been designed for a bidirectional flow of energy between the EV and the charging points in where the vehicles are connected. This opens new doors to the V2G (Vehicle to grid) and to the V2H (Vehicle to home), giving the opportunity not only to charge the vehicles but also use the energy stored in these vehicles for the situations needed, such as improve the grid stability, the use of microgrids and the money saving for the vehicle’s owners. The study was conducted in AirSon a company found in Ängelholm, Sweden. For the study, several parts were developed. First data acquisition for detailed knowledge of the electrical consumes of the company was done. Then a simulation of production of a photovoltaic installation was done in order to integrate this system into the company and help to feed the charge of the long-term parking with renewable energies. In third place a discussion of how the parking could be developed was held as well as the study of the viability of this.  In the results some interesting data has been obtained. In first place from the analysis of the consumes of AirSon the figures representing the electricity usage of each building have been obtained. In second place the calculous of three different photovoltaic installations in different areas is made, obtaining the production per month and hour in each area. Obtaining a total production during June of 37.1 MWh being the month with most production and 2.6 MWh in December being this the month with least production rate. Finally in the results the estimation of the SoC (State of charge) of the cars that arrive to AirSon is found, obtaining an average of 5.37 kWh less energy than the total capacity of the battery at the arrival moment, this means that for completely charge the car the installation needs to provide this 5.37 kWh to each car. Once the energy is delivered into the cars, the parking will be able to take back electricity from the cars in case of necessity of the grid. However, the system will never take more energy from the cars than the one delivered for charging them, due to the parking statement of ensure at least the same energy to the vehicles than the one at the arrival moment. After analysing the results, the key issues are found, such as the weather dependence, the early stage of the technologies and the battery degradation as well as the big investment that needs to be done for having enough energy for the parking to work. Concluding this work with the idea that there is a big potential for the job to work but there are big barriers that need to be overcome first.
519

Optimization of the control process in residential buildings using technological tools

Prat, Joaquin, Romero, Alvaro, Rodriguez, Sandra, Farje, Julio 30 September 2020 (has links)
Many construction companies worldwide continue to implement different methodologies to optimize time and improve management in the execution of works; however, a lack of control in projects continues to be observed. For this reason, one of the most common problems currently is the incompletion of scheduled work. Due to this, it is necessary to keep better control of the projects at the execution stage so that the contractor can optimally, quickly, and easily manage the progress of all the specialties involved. In this sense, this research develops the use of the Plan Grid Application for data collection in the field and the Power Bi software for the automatic processing and information visualization through a management dashboard where indicators are shown to reflect the progress and actual performance of the activities as well as the main non-compliance causes, which leads to optimize the control process and the time spent by its administrators to carry out this management.
520

Detekce distančních mřížek na palivovém souboru / Detection of grids on nuclear fuel set images

Palášek, Jan January 2021 (has links)
Visual inspection of fuel assemblies is necessary to identify potential anomalies in their behaviour associated with their condition and their future usage. One of the possible find- ings are foreign objects caught on the fuel spacer grid which can disrupt the cladding of fuel rods during the operation. The goal of this thesis is to accurately segment the spacer grid from an image, which is a task dual to the foreign object detection, and therefore to automate visual inspection process in this area. We created new datasets covering typical problems appearing on the fuel assembly. To perform the segmentation, we em- ployed neural networks. We increased performance by data augmentation techniques and domain-specific output post-processing. We also measured the algorithm's performance by a newly introduced Line Distance metric, computing the size of the maximum un- certain area between the actual and the predicted transition between grids and rods. In the experiments, we found the best hyperparameters and reached very good results, outperforming our predecessor's algorithm by having three times lower Line Distance metric. 1

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