Global ETD Search

71	Vision based control and landing of Micro aerial vehicles / Visionsbaserad styrning och landning av drönare Karlsson, Christoffer January 2019 (has links) This bachelors thesis presents a vision based control system for the quadrotor aerial vehicle,Crazy ie 2.0, developed by Bitcraze AB. The main goal of this thesis is to design andimplement an o-board control system based on visual input, in order to control the positionand orientation of the vehicle with respect to a single ducial marker. By integrating a cameraand wireless video transmitter onto the MAV platform, we are able to achieve autonomousnavigation and landing in relatively close proximity to the dedicated target location.The control system was developed in the programming language Python and all processing ofthe vision-data take place on an o-board computer. This thesis describes the methods usedfor developing and implementing the control system and a number of experiments have beencarried out in order to determine the performance of the overall vision control system. Withthe proposed method of using ducial markers for calculating the control demands for thequadrotor, we are able to achieve autonomous targeted landing within a radius of 10centimetres away from the target location. / I detta examensarbete presenteras ett visionsbaserat kontrollsystem for dronaren Crazy ie 2.0som har utvecklats av Bitcraze AB. Malet med detta arbete ar att utforma och implementeraett externt kontrollsystem baserat pa data som inhamtas av en kamera for att reglera fordonetsposition och riktning med avseende pa en markor placerad i synfaltet av kameran. Genom attintegrera kameran tillsammans med en tradlos videosandare pa plattformen, visar vi i dennaavhandling att det ar mojligt att astadkomma autonom navigering och landning i narheten avmarkoren.Kontrollsystemet utvecklades i programmeringsspraket Python och all processering avvisions-datan sker pa en extern dator. Metoderna som anvands for att utvecklakontrollsystemet och som beskrivs i denna rapport har testats under ett ertal experiment somvisar pa hur val systemet kan detektera markoren och hur val de olika ingaendekomponenterna samspelar for att kunna utfora den autonoma styrningen. Genom den metodsom presenteras i den har rapporten for att berakna styrsignalerna till dronaren med hjalp avvisuell data, visar vi att det ar mojligt att astadkomma autonom styrning och landning motmalet inom en radie av 10 centimeter. vision control system quadcopter python camera vision based landning crazyflie optical visual odometry odometry transformation ArUco Kalman filter PID marker rigid transformations drone transform control system homogenous transformation ORB detection marker detection Drönare kontroll system kontrollsystem quadcopter quadrocopter kamera vision visionsbaserad styrning landning crazyflie optisk transform homogen transform ORB detektering markör Elektroteknik och elektronik
72	Určení parametrů pohybu ze snímků kamery / Determination of Motion Parameters in Machine Vision Dušek, Stanislav January 2009 (has links) This thesis describe about determination of camera motion parameters in plane. At first there are introduce the basics of motion tracking, is focused to find out displacement between two input images. Below is describe the algorithm GoodFeatruresToTrack, which find out the most significant point in a first image. The point is search out the good point, which will be easy to track in next image, reduce the data volume and prepare the input information (array of significant point) for the algorithm Lucas-Kanade optical flow. In second part is deal with processing and utilization estimations optical flow. There is median filtration, below is describe computation of homogenous transformation, which describe all affine transformation in affine space. As the result are coordinates, which describe the shift between the two input images as X-axis and Y-axis value. The project used the library Open Computer Vision.
73	Návrh malé víceúčelové nádrže v k.ú Velké Albrechtice / Design of a small multipurpose reservoir in the cadastral area Velké Albrechtice Novák, Radomír January 2014 (has links) The first section of this diploma thesis pursues an algorithm design of flood wave transformation in Excel software and its application afterwards. The software is used to design a small multipurpose reservoir. The algorithm covers consumption calculations of typical dam structures such as discharge structures, sluice planks, narrowed section of discharge pipes and safety spillways. The thesis also includes a mathematical model of water infiltration into the bottom of the inundation area and through the dam body. The last section of the thesis is dealing with an aesthetic integration of the whole structure into the local environment.
74	SurvSec Security Architecture for Reliable Surveillance WSN Recovery from Base Station Failure Megahed, Mohamed Helmy Mostafa 30 May 2014 (has links) Surveillance wireless sensor networks (WSNs) are highly vulnerable to the failure of the base station (BS) because attackers can easily render the network useless for relatively long periods of time by only destroying the BS. The time and effort needed to destroy the BS is much less than that needed to destroy the numerous sensing nodes. Previous works have tackled BS failure by deploying a mobile BS or by using multiple BSs, which requires extra cost. Moreover, despite using the best electronic countermeasures, intrusion tolerance systems and anti-traffic analysis strategies to protect the BSs, an adversary can still destroy them. The new BS cannot trust the deployed sensor nodes. Also, previous works lack both the procedures to ensure network reliability and security during BS failure such as storing then sending reports concerning security threats against nodes to the new BS and the procedures to verify the trustworthiness of the deployed sensing nodes. Otherwise, a new WSN must be re-deployed which involves a high cost and requires time for the deployment and setup of the new WSN. In this thesis, we address the problem of reliable recovery from a BS failure by proposing a new security architecture called Surveillance Security (SurvSec). SurvSec continuously monitors the network for security threats and stores data related to node security, detects and authenticates the new BS, and recovers the stored data at the new BS. SurvSec includes encryption for security-related information using an efficient dynamic secret sharing algorithm, where previous work has high computations for dynamic secret sharing. SurvSec includes compromised nodes detection protocol against collaborative work of attackers working at the same time where previous works have been inefficient against collaborative work of attackers working at the same time. SurvSec includes a key management scheme for homogenous WSN, where previous works assume heterogeneous WSN using High-end Sensor Nodes (HSN) which are the best target for the attackers. SurvSec includes efficient encryption architecture against quantum computers with a low time delay for encryption and decryption, where previous works have had high time delay to encrypt and decrypt large data size, where AES-256 has 14 rounds and high delay. SurvSec consists of five components, which are: 1. A Hierarchical Data Storage and Data Recovery System. 2. Security for the Stored Data using a new dynamic secret sharing algorithm. 3. A Compromised-Nodes Detection Algorithm at the first stage. 4. A Hybrid and Dynamic Key Management scheme for homogenous network. 5. Powerful Encryption Architecture for post-quantum computers with low time delay. In this thesis, we introduce six new contributions which are the followings: 1. The development of the new security architecture called Surveillance Security (SurvSec) based on distributed Security Managers (SMs) to enable distributed network security and distributed secure storage. 2. The design of a new dynamic secret sharing algorithm to secure the stored data by using distributed users tables. 3. A new algorithm to detect compromised nodes at the first stage, when a group of attackers capture many legitimate nodes after the base station destruction. This algorithm is designed to be resistant against a group of attackers working at the same time to compromise many legitimate nodes during the base station failure. 4. A hybrid and dynamic key management scheme for homogenous network which is called certificates shared verification key management. 5. A new encryption architecture which is called the spread spectrum encryption architecture SSEA to resist quantum-computers attacks. 6. Hardware implementation of reliable network recovery from BS failure. The description of the new security architecture SurvSec components is done followed by a simulation and analytical study of the proposed solutions to show its performance. Surveillance Wireless Sensor Network Security manager (SM) Backup security manager (BKSM) Network trustworthiness Efficient dynamic secret sharing Distributed users tables (DUT) Node compromise attack Hybrid key management Dynamic key management Homogenous network High end Sensor Nodes (HSNs) Network scalability Network connectivity Unpredictability principal PRNG Resistant to quantum computer
75	SurvSec Security Architecture for Reliable Surveillance WSN Recovery from Base Station Failure Megahed, Mohamed Helmy Mostafa January 2014 (has links) Surveillance wireless sensor networks (WSNs) are highly vulnerable to the failure of the base station (BS) because attackers can easily render the network useless for relatively long periods of time by only destroying the BS. The time and effort needed to destroy the BS is much less than that needed to destroy the numerous sensing nodes. Previous works have tackled BS failure by deploying a mobile BS or by using multiple BSs, which requires extra cost. Moreover, despite using the best electronic countermeasures, intrusion tolerance systems and anti-traffic analysis strategies to protect the BSs, an adversary can still destroy them. The new BS cannot trust the deployed sensor nodes. Also, previous works lack both the procedures to ensure network reliability and security during BS failure such as storing then sending reports concerning security threats against nodes to the new BS and the procedures to verify the trustworthiness of the deployed sensing nodes. Otherwise, a new WSN must be re-deployed which involves a high cost and requires time for the deployment and setup of the new WSN. In this thesis, we address the problem of reliable recovery from a BS failure by proposing a new security architecture called Surveillance Security (SurvSec). SurvSec continuously monitors the network for security threats and stores data related to node security, detects and authenticates the new BS, and recovers the stored data at the new BS. SurvSec includes encryption for security-related information using an efficient dynamic secret sharing algorithm, where previous work has high computations for dynamic secret sharing. SurvSec includes compromised nodes detection protocol against collaborative work of attackers working at the same time where previous works have been inefficient against collaborative work of attackers working at the same time. SurvSec includes a key management scheme for homogenous WSN, where previous works assume heterogeneous WSN using High-end Sensor Nodes (HSN) which are the best target for the attackers. SurvSec includes efficient encryption architecture against quantum computers with a low time delay for encryption and decryption, where previous works have had high time delay to encrypt and decrypt large data size, where AES-256 has 14 rounds and high delay. SurvSec consists of five components, which are: 1. A Hierarchical Data Storage and Data Recovery System. 2. Security for the Stored Data using a new dynamic secret sharing algorithm. 3. A Compromised-Nodes Detection Algorithm at the first stage. 4. A Hybrid and Dynamic Key Management scheme for homogenous network. 5. Powerful Encryption Architecture for post-quantum computers with low time delay. In this thesis, we introduce six new contributions which are the followings: 1. The development of the new security architecture called Surveillance Security (SurvSec) based on distributed Security Managers (SMs) to enable distributed network security and distributed secure storage. 2. The design of a new dynamic secret sharing algorithm to secure the stored data by using distributed users tables. 3. A new algorithm to detect compromised nodes at the first stage, when a group of attackers capture many legitimate nodes after the base station destruction. This algorithm is designed to be resistant against a group of attackers working at the same time to compromise many legitimate nodes during the base station failure. 4. A hybrid and dynamic key management scheme for homogenous network which is called certificates shared verification key management. 5. A new encryption architecture which is called the spread spectrum encryption architecture SSEA to resist quantum-computers attacks. 6. Hardware implementation of reliable network recovery from BS failure. The description of the new security architecture SurvSec components is done followed by a simulation and analytical study of the proposed solutions to show its performance. Surveillance Wireless Sensor Network Security manager (SM) Backup security manager (BKSM) Network trustworthiness Efficient dynamic secret sharing Distributed users tables (DUT) Node compromise attack Hybrid key management Dynamic key management Homogenous network High end Sensor Nodes (HSNs) Network scalability Network connectivity Unpredictability principal PRNG Resistant to quantum computer
76	Změna třídního klimatu po odchodu žáků na osmiletá gymnázia / The Change of Classroom Climate in Czech Elementary Schools with the Departure of Students into High-Track Schools Holubová, Markéta January 2018 (has links) The aim of the dissertation is to compare the psychosocial climate of the classes between the 5th and 6th grades of Czech elementary school. In the train of pupils' leaving into the high- tracked schools there are significant organizational changes in the classes of the 6th grade. This theme includes the phenomenon of the early tracking, when some pupils can leave the mainstream of education (elementary school) and start attending the high-tracked schools (multi-year gymnasium). The aim of our study is to contribute to the research, that with the departure of students into high-tracked schools the psychosocial climate in the classes of the 6th grade unequivocally exacerbates. We are also interested in which specific students are accepted into high-tracked schools, and whether they are effective classroom leaders and socio- metric stars. In our study, we also find out the classroom positions of students who are continuously educated in the 5th and 6th grades of the elementary schools and their classmates, who have come as new students into the classes of the 6th grade. In the theoretical section we introduce the foreign and domestic researches which were conducted on the association between tracking and classroom climate. The empirical part inquiries into a detailed analysis of quantitative research...
77	Uberwindung der Milieufixierung in Freien evangelischen Gemeinden in Deutschland: ein vergleich aktueller ekklesiologischer Entwurfe / Breaking through the fixation of the social milieu of free evangelical churches in Germany: a comparison of current ecclesiological models Endlich, Markus January 2020 (has links) Text in German with summaries in German, English and Afrikaans / Bibliography (pages 133-140) / Die vorliegende Arbeit beschäftigt sich mit der Milieufixierung der Gemeinden des Bundes Freier evangelischer Gemeinden in Deutschland, ihren möglichen inneren und äußeren Ursachen und deren Überwindung durch aktuelle oikodomische Entwürfe. Dazu werden zunächst die Auswirkungen der Milieufixierung anhand der Mitgliederentwicklung und des eingeschränkten Konversionswachstums sowie des Stagnierens und Eingehens von Gemeinden nachgezeichnet. In einem zweiten Schritt werden mögliche Ursachen anhand der Geschichte und der spezifischen Ekklesiologie und Organisationsstruktur Freier evangelischer Gemeinden diskutiert und die sozialen Veränderungen innerhalb der bundesdeutschen Gesellschaft der letzten Jahrzehnte, insbesondere die Herausbildung von Milieus, aufgezeigt. Der Hauptteil der Arbeit besteht in der systematischen Analyse und dem Vergleich von fünf oikodomischen Modellen, die innerhalb des Bundes Freier evangelischer Gemeinden Anwendung finden. Verglichen wird hier insbesondere die milieuüberwindende Potenz dieser Entwürfe. Abschließend werden in Form von sechs Thesen mögliche hilfreiche Schlussfolgerungen für den praktischen Gemeindebau im Bund Freier evangelischer Gemeinden gezogen. / The study discusses the milieu fixation found in the Free Evangelical Churches in Germany, the potential internal and external causes of it and asks how milieu fixation might be overcome by current oikodomic strategies. The effects of milieu fixation are evaluated by looking at membership development, slow congregation growth owing to lower levels of conversion, and the reasons for stagnation and decline in congregations. Thereafter the history of specific ecclesiological and organisational structures of Free Evangelical congregations (FeG), as well as the social changes in German society in recent decades, are examined and analysed. A specific focus is placed on identifying possible causes leading to the formation of milieus. The main part of the study consists of a systematic analysis and comparison of five oikodomic models applied in the Federation FeG, together with a comparison of potential models for reversing milieu fixation. Finally, six propositions are laid out to draw a possible conclusion for practically building up the church in the Federation of Free Evangelical Churches. / Hierdie studie bespreek milieufiksasie wat in die Vrye Evangeliese Kerke in Duitsland aangetref word, die potensiële interne en eksterne oorsake daarvan, en hoe milieufiksasie deur huidige oikodomiese strategieë te bowe gekom kan word. Eerstens word die uitwerking van milieufiksasie geëvalueer deur na lidmaatskapontwikkeling, lae gemeentegroei as gevolg van bekering, en redes vir stagnasie en afname in gemeentes te kyk. Daarna word die geskiedenis van spesifieke ekklesiologiese en organisatoriese strukture van Vrye Evangeliese gemeentes (VeG) en die maatskaplike veranderinge in die Duitse samelewing in onlangse dekades bestudeer en ontleed. ’n Spesifieke fokus word geplaas op die identifisering van moontlike oorsake wat tot die vorming van milieus aanleiding kon gegee het. Die belangrikste deel van die studie bestaan uit ’n sistematiese ontleding en vergelyking van vyf oikodomiese modelle wat in die Federasie van VeG toegepas word, ’n vergelyking van potensiële modelle om milieufiksasie om te keer. Ten slotte word ses stellings ontleed om tot ’n moontlike gevolgtrekking vir praktiese kerkbou in die Federasie van Vrye Evangeliese Kerke te kom. / Philosophy, Practical and Systematic Theology / M. Th. (Practical Theology) Milieu Oikodomik Kultur Versöhnung Ekklesiologie Milieufixierung Milieuspreizung Milieuverschiebung Gesellschaft Tradition Urbanität Gesellschaftliche Diversität Postmoderne Homogenius Unit Milieumodelle Soziale Schichten Inkulturation Gesellschaftstransformation Milieu Oikodomics Culture Reconciliation Ecclesiology Milieu fixation Milieu spreading Milieu shifting Society Tradition Urbanity Social diversity Postmodernity Homogenous Milieu models Social layers Inculturation Social transformation Milieuverspreiding Tradisie Milieu Oikodomie Kultuur Versoening Ekklesiologie Milieufiksasie Milieuverskuiwing Samelewing Beleefdheid Maatskaplike diversiteit Postmoderniteit Homogeen Milieumodelle Maatskaplike lae Enkulturasie Maatskaplike transformasie 286.20943 Baptists -- Germany -- Doctrines City churches -- Germany Free churches -- Germany Baptists -- Germany -- Membership

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