My diploma thesis focuses in its theoretical part on the analysis of photovoltaic cells, panels, their properties and defects . Further there are described materials from which the cells and panels are produced today but also there are mentioned materials which could affect the near future. There are also state the methods of measurement of photovoltaic cells . The practical part analyzes selected photovoltaic panels, determines the level of degradation by measurement and calculation with using the intensity of solar radiation. All results are entred into graphs and tables.

Satellite navigation (such as GPS) has become widely successful and is used by billions of users daily. Accuratepositioning and timing has a wide range of applications and is increasingly being integrated in safety criticalsystems such as autonomous operations, traffic management, navigation for airplanes and other vehicles. Thesecurity and vulnerabilities of satellite navigation is however often not considered in the same way as for exampledata security, even though the high efficacy of spoofing with off-the-self software-defined radio (SDR) has beendemonstrated repeatedly. The lack of concern comes partially from the lack of options as satellite navigationauthentication has not previously existed in the civil domain.This work benchmarks the anti-spoofing and signal level measurements of commercial receivers in both simulatedand real-world scenarios and implements additional anti-spoofing measures. The additional anti-spoofingmeasures are implemented using no additional information than what the receiver should already have accessto in any modern commercial vehicle. Upcoming EU regulation 2021/1228 for vehicles used in internationaltransport will also mandate the use of these three anti-spoofing measures by August 2023. Here receiver time isverified by the means of Network Time Protocol (NTP) and real time clock (RTC); receiver motion is verifiedby the means of dead reckoning and inertial measurement unit (IMU); receiver navigation data is verified by themeans of asymmetric cryptography and Galileo Open Service Navigation Message Authentication (OSNMA).The computational overhead is analyzed as well as cost and worldwide Market feasibility. We estimate thateven basic timing devices would only have to perform one NTP request every 17 days and a microcontrollerpowerful enough to do OSNMA costs less than $2. Finally, the benefits of multi-band receivers and futuredevelopments in both the user and space segments are discussed.

The project focuses on the packaging process of the smart card manufacturing industry. The idea of the project concerns how to increase production packaging efficiency by introducing a control system. After taking an in-depth look at the current production environment, the following system goals were defined: packaging time reduction, cost reduction, decrease in human errors, and reducing the number of customer complaints. To achieve these goals, the thesis project was divided into the following tasks: discovering a feasible solution, actual system development, testing, and evaluation. The proposed system is based on hardware (i.e. barcode scanner, and barcode printer) integrated with customized control software. The barcode scanner acts as a bridge between the system and the production process by scanning a barcode printed on each product. The system prints the required information label for the product’s package according to the scanned product. This label is pasted on the product’s box and is used as a tracking tool during further production steps. The system is very flexible and suits any packaging model. Other functional properties maintained in the system include data security, product traceability, and real time production monitoring. Testing of the system was done in an actual production environment at an Oberthur Technologies manufacturing site. Two production lines were selected to test the system’s functionality, specifically the SIM card production packaging line and the Scratch card/ Bank Card production packaging line. The results obtained during the evaluation phase of the proposed system show that the proposed solution decreased the packaging processing time by (27.3%) over the previous values. Moreover, the resulting human error rate is close to (zero%). / Projektet fokuserar på förpackningen processen smartkortet tillverkningsindustrin. Tanken med projektet handlar om hur att öka effektiviteten produktionen förpackningar genom att införa ett styrsystem. Efter att ha tagit en fördjupad titt på den nuvarande produktionsmiljö, var följande systemkrav mål definieras: nedsättning förpackning tid, minskade kostnader, minskad mänskliga fel och minska antalet kundklagomål. För att uppnå dessa mål var examensarbetet indelad i följande uppgifter: att upptäcka en genomförbar lösning, faktisk systemutveckling, testning och utvärdering. Det föreslagna systemet bygger på hårdvara (dvs streckkodsläsare och streckkod skrivare) integreras med skräddarsydd styrprogram. Den streckkodsläsare fungerar som en bro mellan systemet och produktionsprocessen genom att läsa en streckkod tryckt på varje produkt. Systemet skriver den erforderliga informationen etiketten för produktens förpackning enligt den scannade produkten. Denna etikett klistras in på produktens ask och används som ett verktyg för spårning under ytterligare produktionssteg. Systemet är mycket flexibelt och passar varje förpackning modell. Andra funktionella egenskaper bibehålls i systemet inkluderar datasäkerhet, spårbarhet och i realtid övervakning av produktionen. Testning av systemet gjordes i en verklig produktionsmiljö i ett Oberthur Technologies tillverkningsanläggning. Två produktionslinjer valdes för att testa systemets funktionalitet, särskilt i SIM-kortet produktionen förpackning linje och skrapkort / Bank kortproduktion förpackningslinje. De resultat som erhållits under utvärderingsfasen av det föreslagna systemet visar att den föreslagna lösningen minskade tiden förpackningen behandling av (27,3 %) jämfört med föregående värden. Dessutom är den resulterande mänskliga fel som ligger nära (noll %).

Social Entrepreneurship and Social Enterprises are an emerging trend. An increasing number of individuals are finding ways to address a social issue through their entrepreneurial skills. As well as increasing number of corporations and investing organizations are looking for ventures that address a social issue to fulfill their social responsibility. Thus, it is increasingly becoming important for the social entrepreneurs to measure and report their impacts to society in an accurate way. This research seeks to find out the challenges faced by social entrepreneurs while setting up social impact measurements in their ventures and the solutions adopted by them. Through a series of semi‐structured interviews with successful social entrepreneurs, this research collects qualitative data that increases the knowledge in this area and contributes in a better understanding of the challenges faced by social entrepreneurs. This research found that Theory Of Change is the most commonly used method and is preferred by practitioners as it is easy to implement. The research summarises the efforts it takes to implement the measurements, recommends best practices or advice to make impact measurement easier and useful. Also, a framework is developed that can be used in setting up measurements in a social venture.

Магистерская диссертация состоит из введения, трех глав, заключения, списка литературы и приложений. В работе рассмотрены теоретико-прикладные аспекты создания тепличных комплексов в России. Проанализирован район расположения планируемого тепличного комплекса, рассмотрены основные представленные тепличные комплексы по выращиванию овощной продукции в защищенном грунте. Определены источники финансирования, сформирован бюджет проекта, рассчитаны показатели экономической эффективности проекта. В заключении сформулированы основные выводы и обобщены результаты исследования. / The master's thesis consists of three chapters, conclusion, list of references and applications. The paper considers the theoretical and applied aspects of creating greenhouse complexes in Russia. The location area of the proposed greenhouse complex is analyzed, the main heat-producing complexes represented by heat for growing vegetables in sheltered soil are considered. Sources of financing have been identified, a project budget has been formed, and indicators of the project's economic efficiency have been calculated. In conclusion, the main conclusions are formulated and the research results are summarized.

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In this dissertation, we discuss the Distributed Spacecraft Attitude Control System Simulator (DSACSS) testbed developed at Virginia Polytechnic Institute and State University for the purpose of investigating various control techniques for single and multiple spacecraft. DSACSS is comprised of two independent hardware-in-the-loop simulators and one software spacecraft simulator. The two hardware-in-the-loop spacecraft simulators have similar subsystems as flight-ready spacecraft (e.g. command and data handling; communications; attitude determination and control; power; payload; and guidance and navigation). The DSACSS framework is a flexible testbed for investigating a variety of spacecraft control techniques, especially control scenarios involving coupled attitude and orbital motion. The attitude hardware simulators along with numerical simulations assist in the development and evaluation of Lyapunov based asymptotically stable, nonlinear attitude controllers with three reaction wheels as the control device. The angular rate controller successfully tracks a time varying attitude trajectory. The Modified Rodrigues Parmater (MRP) attitude controller results in successfully tracking the angular rates and MRP attitude vector for a time-varying attitude trajectory. The attitude controllers successfully track the reference attitude in real-time with hardware similar to flight-ready spacecraft. Numerical simulations and the attitude hardware simulators assist in the development and evaluation of a robust, asymptotically stable, nonlinear attitude controller with three reaction wheels as the actuator for attitude control. The MRPs are chosen to represent the attitude in the development of the controller. The robust spacecraft attitude controller successfully tracks a time-varying reference attitude trajectory while bounding system uncertainties. The results of a Global Positioning System (GPS) hardware-in-the-loop simulation of two spacecraft flying in formation are presented. The simulations involve a chief spacecraft in a low Earth orbit (LEO), while a deputy spacecraft maintains an orbit position relative to the chief spacecraft. In order to maintain the formation an orbit correction maneuver (OCM) for the deputy spacecraft is required. The control of the OCM is accomplished using a classical orbital element (COE) feedback controller and simulating continual impulsive thrusting for the deputy spacecraft. The COE controller requires the relative position of the six orbital elements. The deputy communicates with the chief spacecraft to obtain the current orbit position of the chief spacecraft, which is determined by a numerical orbit propagator. The position of the deputy spacecraft is determined from a GPS receiver that is connected to a GPS hardware-in-the-loop simulator. The GPS simulator creates a radio frequency (RF) signal based on a simulated trajectory, which results in the GPS receiver calculating the navigation solution for the simulated trajectory. From the relative positions of the spacecraft the COE controller calculates the OCM for the deputy spacecraft. The formation flying simulation successfully demonstrates the closed-loop hardware-in-the-loop GPS simulator. This dissertation focuses on the development of the DSACSS facility including the development and implementation of a closed-loop GPS simulator and evaluation of nonlinear feedback attitude and orbit control laws using real-time hardware-in-the-loop simulators. / Ph. D.

The astronomical increase in the number of wireless devices such as smart phones in 21th century has revolutionized the way people communicate with one another and share information. The new wireless technologies have also enabled researchers to collect real data about how people move and meet one another in different social settings. Understanding human mobility has many applications in different areas such as traffic planning in cities and public health studies of epidemic diseases. In this thesis, we study the fundamental properties of human contact graphs in order to characterize how people meet one another in different social environments. Understanding human contact patterns in return allows us to propose a cost-effective routing algorithm for spreading information in Delay Tolerant Networks. Furthermore, we propose several contact predictors to predict the unobserved parts of contact graphs when only partial observations are available. Our results show that we are able to infer hidden contacts of real contact traces by exploiting the underlying properties of contact graphs. In the last few years, we have also witnessed an explosion in the number of people who use social media to share information with their friends. In the last part of this thesis, we study the running times of several information spreading algorithms in social networks in order to find the fastest strategy. Fast information spreading has an obvious application in advertising a product to a large number of people in a short amount of time. We prove that a fast information spreading algorithm should efficiently identify communication bottlenecks in order to speed up the running time. Finally, we show that sparsifying large social graphs by exploiting the edge-betweenness centrality measure can also speed up the information spreading rate. / Graduate

Η διπλωματική εργασία διαπραγματεύεται την εφαρμοσιμότητα του peer-to-peer υπολογισμού και τεχνικών στα ασύρματα κινητά ad-hoc δίκτυα και στα δίκτυα αισθητήρων. Παρουσιάζεται μια παραλλαγή ενός νέου P2P πρωτοκόλλου (Energy Level Distributed Tree) που σαν κύρια λειτουργία του έχει την αύξηση του προσδόκιμου λειτουργίας ενός δικτύου αισθητήρων. Επίσης, γίνεται αναφορά στα πιο δημοφιλή εργαλεία προσομοίωσης για P2P πρωτόκολλα δρομολόγησης και παρουσιάζεται ένα νέο εργαλείο, d-p2p-sim, με δυνατότητα προσομοίωσης εκατομμυρίων κόμβων. Τέλος, εξετάζουμε την απόδοση ενός νέου P2P πρωτοκόλλου δρομολόγησης, του Nested Balanced Distributed Tree, που απαντά με βέλτιστο τρόπο ερωτήμα ακριβούς ταιριάσματος και ερωτήματα διαστήματος παρουσιάζοντας παράλληλα δύο νέους αλγορίθμους αναζήτησης για αυτό. / In this master thesis we study the applicability of the peer-to-peer computing and techniques on wireless ad-hoc networks and sensor-nets. We propose a simplified mapping of an optimal P2P protocol (NBDT) onto sensor-nets, the so called Energy Level Distributed Tree (ELDT), which has one main operation: the life expectancy of a sensor-net. Furthermore, are examined the most popular Peer-to-Peer simulators and is presented a new distributed simulator for P2P routing algorithms. The key feature of the proposed simulator is the ability to simulate millions of peers. Finally, is presented a revised version of the NBDT protocol which is hot-spot free and achieves a better load distribution introducing a negligible routing overhead.