• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 470
  • 176
  • 104
  • 64
  • 59
  • 40
  • 21
  • 10
  • 8
  • 8
  • 6
  • 6
  • 6
  • 5
  • 4
  • Tagged with
  • 1142
  • 190
  • 156
  • 151
  • 131
  • 126
  • 124
  • 96
  • 93
  • 88
  • 82
  • 79
  • 74
  • 63
  • 61
  • 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.
91

A Fast Fluid Simulator Using Smoothed-Particle Hydrodynamics

January 2012 (has links)
abstract: This document presents a new implementation of the Smoothed Particles Hydrodynamics algorithm using DirectX 11 and DirectCompute. The main goal of this document is to present to the reader an alternative solution to the largely studied and researched problem of fluid simulation. Most other solutions have been implemented using the NVIDIA CUDA framework; however, the proposed solution in this document uses the Microsoft general-purpose computing on graphics processing units API. The implementation allows for the simulation of a large number of particles in a real-time scenario. The solution presented here uses the Smoothed Particles Hydrodynamics algorithm to calculate the forces within the fluid; this algorithm provides a Lagrangian approach for discretizes the Navier-Stockes equations into a set of particles. Our solution uses the DirectCompute compute shaders to evaluate each particle using the multithreading and multi-core capabilities of the GPU increasing the overall performance. The solution then describes a method for extracting the fluid surface using the Marching Cubes method and the programmable interfaces exposed by the DirectX pipeline. Particularly, this document presents a method for using the Geometry Shader Stage to generate the triangle mesh as defined by the Marching Cubes method. The implementation results show the ability to simulate over 64K particles at a rate of 900 and 400 frames per second, not including the surface reconstruction steps and including the Marching Cubes steps respectively. / Dissertation/Thesis / M.S. Computer Science 2012
92

Implementace simulátoru DEVS v C++20 / DEVS Simulator Implementation in C++20

Šurina, Timotej January 2021 (has links)
This master's thesis deals with the issue of modeling and simulation of systems based on the DEVS formalism. The result of this work is a library that is inspired by the adevs tool and based on the classical DEVS formalism. The library is implemented in the programming language C++20 and is supplemented by predefined models of components for creation of queueing systems. The library also contains a set of examples for use in teaching. In comparison with the paralel adevs tool it is less effective but it has simpler interface with focus on clarity, which is more important for teaching. The library also simplifies definition of models with the use of modules, intelligent pointers for memory management and the use of mentioned components.
93

Simulátor určení souřadnic senzorových uzlů / Performance of Anchor-Free Localization in Wireless Sensor Network

Nováček, Aleš January 2010 (has links)
Many applications that use senzor data from a wireless senzor network require corresponding node position information as well, information from the senzors is useful only if node location information is also available. There are many ways to get information about location of senzor, but some are expensive and inefficient. My work presents fully decentralized algorithm AFL (anchor-free localization) for localization of wireless sensors. Aim of my master´s thesis is to describe main features and advantages of AFL and to create program that simulates localization process.
94

Zdroj nosného kmitočtu pro přenosný simulátor radiolokačních signálů / Carrier Frequency Generator for Portable Radar Signal Simulator

Filip, Martin January 2010 (has links)
This thesis deals with the analysis and solution source for carrier frequency generator for portable radar signal simulator. This simulator is tunable in the frequency range from 2 GHz to 18 GHz and as it´s frequency source generator is used YIG oscillator for its very high frequency realignment. Simulator provides output power up to 1W on the SMA connector which can be connect to internal antenna by using jumper cable. To achieve this output power will be used by semiconductor amplifier.
95

Simulátor slunečního záření / Solar radiation simulator

Kalas, Ladislav January 2011 (has links)
This master's thesis is focused on properties of direct solar radiation, diffuse radiation and their usage in solar systems. Goal of this paper is to compare the different sources of light with the radiation and selection source for the solar radiation simulator, followed by a measuring device for homogeneous distribution of solar radiation and implemantation of solar simulator.
96

A Visually Realistic Simulator for Autonomous eVTOL Aircraft

Nielsen, Seth M. 21 December 2021 (has links)
Electrically powered vertical takeoff and landing (eVTOL) aircraft could provide a new mode of air transportation of people and cargo that is low-cost, on-demand, and able to reach more areas than is possible with current technology. They have the unique ability to takeoff and land in congested spaces yet efficiently travel long distances which makes them a promising technology for applications such as rapid medical assistance, automated package delivery, or human transportation. This type of aircraft has only recently become a possibility, owing to advancements in battery technology, computing power, and sensor technologies, and thus support for eVTOLs is lacking among high-fidelity graphics simulation software. High-fidelity graphics are important for the goal of fully autonomous eVTOL aircraft in order to accurately simulate vision-based navigation using camera sensors. In this work, we present VTOL-AirSim, an extension of Microsoft AirSim with full integration of a tiltrotor eVTOL aircraft. Built on Unreal Engine, a high-end graphics game engine, it includes photorealistic graphics for simulated camera images and for high-quality presentations. We created the visual components of a fully animated tiltrotor vehicle and a detailed city environment for it to fly in. The tiltrotor can be controlled via motor PWM commands, by overriding its state in the world with the use of an external dynamics simulation, or by using the PX4 Autopilot. We give a tutorial on how to use VTOL-AirSim where we provide examples for each method of control, including scripts for controlling the tiltrotor via a geometric controller and control allocation module developed by others in the BYU MAGICC Lab. We also show how to further develop VTOL-AirSim, and how to add custom aircraft or custom environments so that others may use it in their own research.
97

An FMI-compliant process tracking simulator of a multi-effect evaporation plant

Björklund, Ludvig January 2020 (has links)
<p>Distanspresentation.</p>
98

Consequences of GIS Classification Errors on Bias and Variance of Forest Inventory Estimates

Crosby, Michael Keith 30 April 2011 (has links)
The use of remotely sensed imagery (e.g. Landsat TM) for developing forest inventory strata has become increasingly more common in recent years as data have become more readily available. Errors are inherent with the use of this technology, either from user mis-classification of conditions represented in the imagery or due to flaws in the technology. Knowledge of these errors is important, as they can inflate the variance of inventory estimates. Forest inventory estimates from the Mississippi Institute for Forest Inventory (MIFI) were applied to determine the extent that classification errors affect volume and area estimates. Forest strata (e.g. hardwood, mixed, and pine) determined by the classification of imagery and used for inventory design were compared with field verification data obtained during the inventory. Mis-classified plots were reallocated to their correct strata and both area and volume estimates were obtained for both scenarios (i.e. mis-classified and correctly classified plots). The standard error estimates for mean and total volume decreased when plots were re-allocated to their correct strata. Mis-classification scenarios were then performed, introducing various levels of mis-classification in each stratum. When the scenarios were performed for the Doyle volume unit the statistical efficiencies were larger than for cubic foot volume. Care should be taken when utilizing moderate resolution satellite imagery such as Landsat TM as image mis-classification could lead to large losses in the precision of volume estimates. The increased efficiency obtained from a correct classification/forest stratification scheme, as demonstrated here, could lead to the exploration of additional image classification methods or the use of higher resolution satellite data. Knowledge of these errors in advance could be useful to investors seeking a minimum-risk area for a forest products mill location.
99

Development of overcurrent relay model and power system simulator using National Instruments devices in real-time

Palla, Sunil Kumar 13 December 2008 (has links)
One of the major objectives at Mississippi State University’s Power and Energy Research Laboratory (PERL) is to develop an adaptive protective controller for Shipboard Power System (SPS) protection. This thesis work focuses on developing an overcurrent relay model in LabVIEW software and validating the developed model by conducting Hardware-in-the-Loop (HIL) tests with Real-Time Digital Simulator (RTDS) and commercial Schweitzer Engineering Laboratories (SEL)-351S directional over-current relay. Simulation results show that the developed relay model is quite flexible, efficient and can be used in real-time. Modeling efforts to establish a HIL platform using National Instruments devices have been presented here. This thesis work also proposes a high-performance and low-cost National Instruments-PXI platform for power system simulations. Two-bus, eight-bus and shipboard power system (SPS) test cases are developed using Matlab/Simulink.Software-in-the-Loop (SIL) tests are conducted for these test cases with Matlab/Simulink overcurrent relay model for several fault conditions. To determine the performance of the NI-PXI system, open loop tests are done between the NI-PXI and the SEL-351S relay and these results are compared with the results of open loop test conducted between the RTDS and SEL-351S relay. HIL tests are done between the NI-PXI system and the dSPACE relay model. HIL tests are also done between the NI-PXI and the commercial SEL-351S relay. These results show that the NI-PXI controller can be used as a power system simulator.
100

Modeling of Vehicle Controller Area Network for Control Systems Simulation

Hegde, Bharatkumar 30 December 2014 (has links)
No description available.

Page generated in 0.0307 seconds