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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.
641

Simulation of Attitude and Orbit Control for APEX CubeSat

de Graaf, Niels January 2020 (has links)
CubeSats are becoming a game changer in the space industry. Appearing first for univer-sity mission, its popularity is increasing for commercial use and for deep space missionssuch as the on HERA mission that will orbit in 2026 around an asteroid as part of aplanetary defence mission. Standardisation and industrial collaboration is key to a fastdevelopment, assuring the product quality and lower development expenditures.In this study the focus is set elaborating a low cost demonstrator platform to be usedfor developing and testing onboard software on physical hardware: a Hardware-Softwaretesting facility. The purpose of such a platform is to create an interactive and accessibleenvironment for developing on board software. The application chosen to be elaboratedon this platform is a module the subsystem of attitude and orbit control of the satelliteorbiting around asteroid.In order to create this platform the simulation of the asteroid environment of theCubeSat has been made using open source software libraries. During this task the per-formance of open source libraries has been compared to commercial alternatives. In thedevelopment of simulation different orbit perturbations have been studied by modellingthe asteroid as a cube or spheroid and additionally the effect of a third perturbing bodyand radiation pressure.As part of this project two microcontroller have been set up communicating using acommunication bus and communication protocols used for space applications to simulatehow the attitude and orbit control is commanded inside the CubeSat.
642

Understanding Cortical Neuron Dynamics through Simulation-Based Applications of Machine Learning

January 2020 (has links)
abstract: It is increasingly common to see machine learning techniques applied in conjunction with computational modeling for data-driven research in neuroscience. Such applications include using machine learning for model development, particularly for optimization of parameters based on electrophysiological constraints. Alternatively, machine learning can be used to validate and enhance techniques for experimental data analysis or to analyze model simulation data in large-scale modeling studies, which is the approach I apply here. I use simulations of biophysically-realistic cortical neuron models to supplement a common feature-based technique for analysis of electrophysiological signals. I leverage these simulated electrophysiological signals to perform feature selection that provides an improved method for neuron-type classification. Additionally, I validate an unsupervised approach that extends this improved feature selection to discover signatures associated with neuron morphologies - performing in vivo histology in effect. The result is a simulation-based discovery of the underlying synaptic conditions responsible for patterns of extracellular signatures that can be applied to understand both simulation and experimental data. I also use unsupervised learning techniques to identify common channel mechanisms underlying electrophysiological behaviors of cortical neuron models. This work relies on an open-source database containing a large number of computational models for cortical neurons. I perform a quantitative data-driven analysis of these previously published ion channel and neuron models that uses information shared across models as opposed to information limited to individual models. The result is simulation-based discovery of model sub-types at two spatial scales which map functional relationships between activation/inactivation properties of channel family model sub-types to electrophysiological properties of cortical neuron model sub-types. Further, the combination of unsupervised learning techniques and parameter visualizations serve to integrate characterizations of model electrophysiological behavior across scales. / Dissertation/Thesis / Doctoral Dissertation Applied Mathematics 2020
643

Training Security Professionals in Social Engineering with OSINT and Sieve

Meyers, Jared James 01 June 2018 (has links)
This research attempts to create a novel process, Social Engineering Vulnerability Evaluation, SiEVE, to use open source data and open source intelligence (OSINT) to perform efficient and effectiveness spear phishing attacks. It is designed for use by "œred teams" and students learning to conduct a penetration test of an organization, using the vector of their workforce. The SiEVE process includes the stages of identifying targets, profiling the targets, and creating spear phishing attacks for the targets. The contributions of this research include the following: (1) The SiEVE process itself was developed using an iterative process to identify and fix initial shortcomings; (2) Each stage of the final version of the SiEVE process was evaluated in an experiment that compared performance of students using SiEVE against performance of those not using SiEVE in order to test effectiveness of the SiEVE process in a learning environment; Specifically, the study showed that those using the SiEVE process (a) did not identify more targets, (b) did identify more information about targets, and (c) did lead to more effective spear phishing attacks. The findings, limitations, and future work are discussed in order to provide next steps in developing formalized processes for red teams and students learning penetration testing.
644

Designing a Simulator for an Electrically-Pumped Organic Laser Diode

Hulbert, Robert 01 June 2019 (has links)
Organic semiconductors provide an alternative set of basis materials to fabricate electronic devices like PN Junctions, LEDs, and FETs. These materials have several benefits over traditional inorganic semiconductors including their mechanical flexibility, reliance on renewable resources, and inexpensive large-scale manufacturability. Despite the contemporary device implementations with organic semiconductors, a solid-state electrically-pumped organic laser diode does not exist. However, organically-based lasers do exist by utilizing the organic material strictly for optical gain. The challenge occurs when charge carriers appear in the organic material. The charge carriers must reach a concentration such that population inversion occurs producing optical gain. However, between the overlapping emission and absorption spectra of the organic material and insufficient carrier concentrations, positive optical gain remains elusive in electrically-pumped organic diodes. Organic device simulation provides a faster method of testing organic materials and device structures for positive optical gain based on known organic physics. The results generated from simulation provide key information in development of physical organic devices. This project produces a simulator capable of modeling current density and optical density with the intent of testing various device structures that allow for lazing in organic materials.
645

Využití Open Source platforem v rámci vzdělávání v oboru Grafický design / Use of Open Source platforms in education in the field of Graphic Design

Lukáš, David January 2021 (has links)
This diploma work is fokused on the opportunities of using the Open Source Programmes in the lessons at secondary vocational schools according to Graphic Design as a branch of study. In the theoretical part are basic terms explained and reachable educational sources and matherials including graphic editor work noticed . There are described the special signs of the Graphic design branch in a context with the secondary vocational school and the goals of education defined inside RVP (Frame Educational Plan). It speaks about the claims, their availability and the chance of their using as a legal area where are needed skills and experiences for students and their work aplication adopted. The practical part is dedicated to the survey of the ways of possible work in graphic editors and opportunities of using alternative graphic editors at each secondary school offering Graphic design as a branch of study. It includes time analysis of the vocational subjects defined in the School Educational Programme, questioner's investigation and interviews with the teachers. The situation in a real practice also with interviews with professionals and exployers are examined there too. We can find many problematic moments connected with the aplication of alternative graphic editors into the education and practice from...
646

Přenosová soustava ČR po roce 2040 / Transmission system of the Czech Republic after 2040

Gabrys, Dominik January 2020 (has links)
This master thesis is focused on issue transimission system of Czech republic after 2040. Thesis is divided in two parts, teoretical and practical. Teoretical part contains present trends of transmission sytem and the most probably changes in the future decade. Practical part contains simulation of Czech transmission system and various scenarios with idea of open source.
647

Testování odolnosti IP PBX proti útokům s využitím testeru Spirent Avlanache / Testing of IP PBX resistance against attacks using Spirent Avalanche tester

Zelenay, Martin January 2015 (has links)
This work explores, analyzes and rate infuence of VoIP attacks on open source pbx functionality. It describes how voice over IP attacks are achieved according to security standards. There are described concepts and basics of VoIP networks with orientation on facts necessary to understand analyzed actions and measurements in theoretical part. In practical part, there is described realization of attack tests according to instructions with first orientation on initial checking of testing device, pbx’s and security attack possibilities and then complex creation and testing of attack scenarios types such as fuzzing and denial of service attacks.
648

Využití procesního řízení v chemické laboratoři / The Utilization of Process Management in Chemistry Laboratory

Franek, Jiří January 2008 (has links)
This diploma thesis deals with application of business process management principles to the order processing in chemical laboratory. In the first section of the work is accounted history and evolution of business process management and launching methodology as well. In further section was analyzed wider neighborhood of the company. It was necessary to find appropriate processes suitable for the optimization. Primary activities were identified using newly modeled value added chain diagram. Primary activities were decomposed to the key processes. These processes were described using event-driven process chain diagrams. Strategic goals were determined by internal and external organization aspects. The influence of the strategic goals on the key processes was evaluated to find a process attributes which can be improved using business process management. The goal of this work was to propose possible solution for the controlling and communication infrastructure allowing operational control over nondeterministic flow of orders and further reporting. The result of this work is new structure of key processes concerning orders and their passing the organization.
649

Problematika elektronického obchodu společnosti / Aspects of Company's E-commerce

Frolichová, Klára January 2010 (has links)
The thesis is focused on the establishment of company's e-commerce. Content of the thesis is a detailed market analysis and possible suppliers of solution, security, law and technology. Part of this work is a proposal for the implementation of e-commerce in company. Thesis is also engaged in internet marketing and SEO optimization.
650

Analýza a návrh Open Source řešení pro Městský úřad Blansko / Analyze of Open Source Solutions for Municipal Office Blansko

Veselý, Jakub January 2010 (has links)
The object of this mater’s thesis is to analyze current situation of information system at municipal office of Blansko and to review it. Subsequently to suggest other possible solutions and improvements. Formulation of economic and other advantages and possible disadvantages and problems that can occur in case of implementation of other OpenSource components.

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