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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.
81

Guideline in prenatal: development of nursing technoloy in the light of CIPE, alpha version / Guia de Conduta em prÃ-natal: desenvolvimento de tecnologia em enfermagem à luz da CIPE, versÃo alfa

Neudson Jonhson Martinho 04 March 2005 (has links)
CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / O enfermeiro obstetra volta ao cenÃrio da saÃde reprodutiva com suas responsabilidades ampliadas, como estratÃgia proposta pela OrganizaÃÃo Mundial da SaÃde â OMS, para a reduÃÃo dos Ãndices de morbi-mortalidade materna e perinatal. Este fato, torna maior a exigÃncia de melhor qualificaÃÃo profissional, para que as intervenÃÃes implementadas para proteÃÃo à saÃde da mulher e da crianÃa sejam efetivas e eficazes. Nesta perspectiva, desenvolvi este estudo documental, objetivando propor um guia de conduta para as aÃÃes clÃnicas dos enfermeiros em consulta prÃ-natal na dimensÃo fisiolÃgica, subsidiado na ClassificaÃÃo Internacional para a PrÃtica de Enfermagem-CIPE. Foi desenvolvido no Centro de Parto Natural, do Centro de Desenvolvimento Familiar (CEDEFAM) da Universidade Federal do Cearà (UFC), localizado na cidade de Fortaleza-CE. A populaÃÃo se constituiu de 253 prontuÃrios de gestantes que se submeteram a consulta de enfermagem em prÃ-natal no perÃodo compreendido entre julho de 2003 a agosto de 2004, e a amostra foi composta por 62 prontuÃrios randomicamente selecionados. Utilizei um instrumento para coleta de dados que continha os fenÃmenos de Enfermagem segundo a CIPE - versÃo alfa. Os dados foram coletados nos meses de maio a agosto de 2004. Detectei que os fenÃmenos mais prevalentes nas gestantes foram: sono intermitente (56,5%); dispnÃia funcional (51,6%); edema (37,1%); ortopnÃia (35,5%) e constipaÃÃo (32,2%). Efetivei os testes de associaÃÃo de qui-quadrado e Firsher, mas nÃo houve associaÃÃo dos fenÃmenos entre si e nem com as demais variÃveis do estudo. O desenvolvimento do guia de conduta me possibilitou verificar que o uso de tecnologias à algo acessÃvel à Enfermagem e que a CIPE pode contribuir para melhor organizaÃÃo das aÃÃes do enfermeiro no prÃ-natal, a partir das respostas das gestantes frente Ãs alteraÃÃes fisiolÃgicas ocasionadas pela gravidez. / The obstetric nurse returns to the scenery of reproductive health with their responsibilities enlarged, as strategy proposed by the World Organization of Health - OMS, for the reduction of the maternal and perinatal mortality rates. This fact increases the demands of better professional qualification, so that the interventions implemented for the protection of womenâs and childrenâs health are effective and efficacious. In this perspective, we developed this documental study, aiming to propose a guideline for the nursesâ clinical actions in prenatal consultations in the physiological dimension, subsidized in the International Classification for the Practice of Nursing-CIPE. It was developed at the Center of Natural Childbirth of the Center of Family Development - CEDEFAM/UFC, located in the city of Fortaleza-CE. The population was constituted of 253 records of pregnant women that attended the prenatal nursing consultation in the period between July 2003 and August 2004, and the sample was composed of 62 records selected at random. We used an instrument for data collection that contained the Nursing phenomena according to the CIPE - alpha version. The data were collected in the months of May and August 2004. We detected that the more prevalent phenomenon in the pregnant women were: intermittent sleep (56,5%); functional dyspnea (51,6%); edema (37,1%); orthopnea (35,5%) and constipation (32,2%). We carried out the tests of association qui-square and Firsher, but there was not association of the phenomenon among themselves, nor with the other variables of the study. The conduct guideâs development made it possible to verify that the construction of technologies is something accessible to Nursing and that the CIPE can contribute to a better organization of the nurseâs actions during prenatal period, starting from the answers of the pregnant women facing the physiological alterations caused by pregnancy
82

An interactive 3D interface for hybrid model specification

Vasilev, Viktor January 2017 (has links)
To ease development and lower the entry barrier for new adopters many development environments offer visual means to edit complex data. Cyber-physical systems are a perfect candidate for such manipulations since they are usually described in the form of isolated, well defined components that can be manipulated individually. The physical parts of such systems often can be directly translated into real world objects and allowing the developer to interact with those in a familiar manner can greatly increase the usability and agility of the development process. In this thesis we focus on the exploration of interactive manipulation of hybrid system models. Our research examines a solution based on the Acumen simulation environment. We describe the tight integration between the textual model and 3D visualisation, go into detailed analysis of the implementation and use case-studies to illustrate concrete applications
83

Characterisation and phase compensation of a coplanar waveguide to coplanar strip line balun

Du Toit, Johannes Bartholomeus 20 August 2010 (has links)
A uniplanar balun that transforms unbalanced coplanar waveguide (CPW) to balanced coplanar strip line (CPS) is characterised through simulation and measurement. By illustrating the effect of many of the critical design parameters, the operation of this balun is discussed and a set of design criteria is defined. The parameter study discusses the size and shape of the radial open, the type and length of the CPW taper and the thickness and type of the bond wires. Newly developed etched bond wires are implemented to provide better manufacturing repeatability and reliability. A complete balun testing procedure is developed and described, consisting of three separate tests. The balun is tested in the normal back-to-back configuration, as a terminated single balun, and the magnitude and phase imbalance is also determined by using a three-port test circuit connected to the balun. The advantages of implementing this full test procedure, and thus fully characterising the balun under test, are emphasised throughout. Results obtained by using this procedure show that the basic balun works well over the full operating band, except for the phase imbalance, which is usable but not optimal. A simple technique to correct the phase imbalance of the balun is introduced, and validated through measurements of the balun connected to the three-port test circuit. As a final validation the balun is connected as feed for an etched dipole antenna for which good impedance matching and pattern results are shown. AFRIKAANS : ’n Enkelvlak balon (BALans-na-ONbalans) wat van ongebalanseerde enkelvlak golfgeleier (CPW) na gebalanseerde enkelvlak strooklyn (CPS) transformeer, word gekarakteriseer deur simulasie en metings. Deur die effek van baie van die kritiese ontwerpsparameters te demonstreer, word die werking van die balon bespreek en ’n stel ontwerpskriteria opgestel. Die parameter studie bespreek die radiale ope struktuur se vorm en grote, die tipe en lengte van die CPW transformator and die dikte en tipe van die konneksie drade. Nuut ontwikkelde geëtste konneksie drade word geïmplementeer om beter vervaardigingsherhaalbaarheid en betroubaarheid te verseker. ’n Volledige balon toetsprosedure word ontwikkel en beskryf en bestaan uit drie aparte toetse. Die balon word getoets in die normale rug-aan-rug konfigurasie, as ’n enkel getermineerde balon en die grote asook fase van die wanbalans word bepaal deur die gebruik van ’n drie-poort toetsbaan wat aan die balon gekoppel word. Die voordele verbonde daaraan om hierdie volledige toetsprosedure toe te pas, en daardeur die balon volledig te karakteriseer, word deurlopend beklemtoon. Die resultate wat hierdie prosedure oplewer wys dat die basiese balon goed werk oor die volledige frekwensieband, behalwe vir die fase-wanbalans parameter, wat bruikbaar, maar nie ideaal is nie. ’n Eenvoudige tegniek om die fase-wanbalans van die balon te korrigeer word bekend gestel en getoets deur die drie-poort toetsbaan weer te gebruik. As ’n finale validasie word die balon aan ’n geëtste dipool gekoppel word, waarvan goeie impedansie aanpassings en patrone gewys word. Copyright / Dissertation (MEng)--University of Pretoria, 2010. / Electrical, Electronic and Computer Engineering / unrestricted
84

Design of a low noise, limited area and full on-chip power management for CMOS pixel sensors in high energy physics experiments / Conception de la gestion de l'alimentation à faible bruit, de petite taille et sur-puce pleinement pour les capteurs à pixels CMOS dans des expériences en physique des hautes énergies

Wang, Jia 03 September 2012 (has links)
Quelles sont les particules élémentaires et comment l'univers proviennent sont les principales forces motrices de la physique des hautes énergies. Afin de démontrer le modèle standard et découvrez la nouvelle physique, plusieurs détecteurs sont construits pour les expériences en physique des hautes énergies. Capteurs à pixels CMOS offrent un compromis attirant entre la vitesse de lecture, le budget matériel, la tolérance au rayonnement, la consommation d'énergie et la granularité, par rapport aux capteurs à pixels hybrides et des dispositifs à transfert de charge. Ainsi, les CPS sont un bon choix pour détecter les particules chargées dans les détecteurs de vertex et des télescopes de faisceau. La distribution de puissance devient un enjeu important dans les détecteurs à venir, puisque une quantité considérable de capteurs seront installés. Malheureusement, le «Independent Powering» échoue, comme l'approche traditionnelle. Afin de résoudre les problèmes de distribution de puissance et de fournir des tensions silencieuses, cette thèse se concentre sur la conception de la gestion de l'alimentation à faible bruit, à basse consommation d'énergie, de petite taille et sur-puce pleinement pour les CPS. Les CPS sont d'abord introduits en tirer les exigences de conception de la gestion de l'alimentation. La distribution de puissance dédiées à les CPS est ensuite proposé, dans laquelle la gestion de l'alimentation est utilisée comme seconde étape de conversion de puissance. Deux régulateurs sur-puce pleinement sont proposés pour générer la tension d'alimentation analogique et de la tension d'alimentation de référence requis par l'opération d'échantillonnage double corrélé, respectivement. Deux prototypes ont vérifié ces régulateurs. Ils peuvent répondre aux exigences des CPS. En outre, les techniques de gestion de l'alimentation et de la conception tolérance au rayonnement sont également présentés dans cette thèse. / What are the elementary particles and how did the universe originate are the main driving forces in the high energy physics. In order to further demonstrate the standard model and discover new physics, several detectors are built for the high energy physics experiments. CMOS pixel sensors (CPS) can achieve an attractive tradeoff among many performance parameters, such as readout speed, granularity, material budget, power dissipation, radiation tolerance and integrating readout circuitry on the same substrate, compared with the hybrid pixel sensors and charge coupled devices. Thus, the CPS is a good candidate for tracking the charged particles in vertex detectors and beam telescopes.The power distribution becomes an important issue in the future detectors, since a considerable amount of sensors will be installed. Unfortunately, the independent powering has been proved to fail. In order to solve the power distribution challenges and to provide noiseless voltages, this thesis focuses on the design of a low noise, limited area, low power consumption and full on-chip power management in CPS chips. The CPS are firstly introduced drawing the design requirements of the power management. The power distribution dedicated to CPS chips is then proposed, in which the power management is utilized as the second power conversion stage. Two full on-chip regulators are proposed to generate the analog power supply voltage and the reference voltage required by correlated double sampling operation, respectively. Two prototypes have verified these regulators. They can meet the requirements of CPS. Moreover, the power management techniques and the radiation tolerance design are also presented in this thesis.
85

SOSLite: Soporte para Sistemas Ciber-Físicos y Computación en la Nube

Pradilla Ceron, Juan Vicente 16 January 2017 (has links)
Cyber-Physical Systems (CPS) have become one of the greatest research topics today; because they pose a new complex discipline, which addresses big existing and future systems as the Internet, the Internet of Things, sensors networks and smart grids. As a recent discipline, there are many possibilities to improve the state of the art, interoperability being one of the most relevant. Thus, this thesis has been created within the framework of interoperability for CPS, by using the SOS (Sensor Observation Service) standard, which belongs to the SWE (Sensor Web Enablement) framework of the OGC (Open Geospatial Consortium). It has been developed to give rise to a new line of research within the Distributed Real-Time Systems and Applications group (SATRD for its acronym in Spanish) from the Communications Department of the Polytechnic University of Valencia (UPV for its acronym in Valencian). The approach, with which the interoperability in the CPS has been addressed, is of synthetic type (from parts to whole), starting from a verifiable and workable solution for interoperability in sensor networks, one of the most significant CPSs because it is integrated in many other CPSs, next adapting and testing the solution in more complex CPS, such as the Internet of Things. In this way, an interoperability solution in sensor networks is proposed based on the SOS, but adapted to some requirements that makes of this mechanism a lighter version of the standard, which facilitates the deployment of future implementations due to the possibility of using limited devices for this purpose. This theoretical solution is brought to a first implementation, called SOSLite, which is tested to determine its characteristic behavior and to verify the fulfillment of its purpose. Analogously, and starting from the same theoretical solution, a second implementation is projected called SOSFul, which proposes an update to the SOS standard so that it is lighter, more efficient and easier to use. The SOSFul, has a more ambitious projection by addressing the Internet of Things, a more complex CPS than sensors networks. As in the case of the SOSLite, tests are performed and validation is made through a use case. So, both the SOSLite and the SOSFul are projected as interoperability solutions in the CPS. Both implementations are based on the theoretical proposal of a light SOS and are available for free and under open source licensing so that it can be used by the research community to continue its development and increase its use. / Los Sistemas Ciber-Físicos (CPS) se han convertido en uno de los temas de investigación con mayor proyección en la actualidad; debido a que plantean una nueva disciplina compleja, que aborda sistemas existentes y futuros de gran auge como: la Internet, la Internet de las Cosas, las redes de sensores y las redes eléctricas inteligentes. Como disciplina en gestación, existen muchas posibilidades para aportar al estado del arte, siendo la interoperabilidad uno de los más relevantes. Así, esta tesis se ha creado en el marco de la interoperabilidad para los CPS, mediante la utilización del estándar SOS (Sensor Observation Service) perteneciente al marco de trabajo SWE (Sensor Web Enablement) del OGC (Open Geospatial Consortium). Se ha desarrollado para dar surgimiento a una nueva línea de investigación dentro del grupo SATRD (Sistemas y Aplicaciones de Tiempo Real Distribuidos) del Departamento de Comunicaciones de la UPV (Universitat Politècnica de València). La aproximación con la cual se ha abordado la interoperabilidad en los CPS es de tipo sintética (pasar de las partes al todo), iniciando desde una solución, verificable y realizable, para la interoperabilidad en las redes de sensores, uno de los CPS más significativos debido a que se integra en muchos otros CPS, y pasando a adaptar y comprobar dicha solución en CPS de mayor complejidad, como la Internet de las Cosas. De esta forma, se propone una solución de interoperabilidad en las redes de sensores fundamentada en el SOS, pero adaptada a unos requerimientos que hacen de este mecanismo una versión más ligera del estándar, con lo que se facilita el despliegue de futuras implementaciones debido a la posibilidad de emplear dispositivos limitados para tal fin. Dicha solución teórica, se lleva a una primera implementación, denominada SOSLite, la cual se prueba para determinar su comportamiento característico y verificar el cumplimiento de su propósito. De forma análoga y partiendo de la misma solución teórica, se proyecta una segunda implementación, llamada SOSFul, la cual propone una actualización del estándar SOS de forma que sea más ligero, eficiente y fácil de emplear. El SOSFul, tiene una proyección más ambiciosa al abordar la Internet de las Cosas, un CPS más complejo que las redes de sensores. Como en el caso del SOSLite, se realizan pruebas y se valida mediante un caso de uso. Así, tanto el SOSLite como el SOSFul se proyectan como soluciones de interoperabilidad en los CPS. Ambas implementaciones parten de la propuesta teórica de SOS ligero y se encuentran disponibles de forma gratuita y bajo código libre, para ser empleados por la comunidad investigativa para continuar su desarrollo y aumentar su uso. / Els sistemes ciberfísics (CPS, Cyber-Physical Systems) s'han convertit en un dels temes de recerca amb major projecció en l'actualitat, a causa del fet que plantegen una nova disciplina complexa que aborda sistemes existents i futurs de gran auge, com ara: la Internet, la Internet de les Coses, les xarxes de sensors i les xarxes elèctriques intel·ligents. Com a disciplina en gestació, hi ha moltes possibilitats per a aportar a l'estat de la qüestió, sent la interoperabilitat una de les més rellevants. Així, aquesta tesi s'ha creat en el marc de la interoperabilitat per als CPS, mitjançant la utilització de l'estàndard SOS (Sensor Observation Service) pertanyent al marc de treball SWE (Sensor Web Enablement) de l'OGC (Open Geospatial Consortium). S'ha desenvolupat per a iniciar una nova línia de recerca dins del Grup de SATRD (Sistemes i Aplicacions de Temps Real Distribuïts) del Departament de Comunicacions de la UPV (Universitat Politècnica de València). L'aproximació amb la qual s'ha abordat la interoperabilitat en els CPS és de tipus sintètic (passar de les parts al tot), iniciant des d'una solució, verificable i realitzable, per a la interoperabilitat en les xarxes de sensors, un dels CPS més significatius pel fet que s'integra en molts altres CPS, i passant a adaptar i comprovar aquesta solució en CPS de major complexitat, com la Internet de les Coses. D'aquesta forma, es proposa una solució d'interoperabilitat en les xarxes de sensors fonamentada en el SOS, però adaptada a uns requeriments que fan d'aquest mecanisme una versió més lleugera de l'estàndard, amb la qual cosa es facilita el desplegament de futures implementacions per la possibilitat d'emprar dispositius limitats a aquest fi. Aquesta solució teòrica es porta a una primera implementació, denominada SOSLite, que es prova per a determinar el seu comportament característic i verificar el compliment del seu propòsit. De forma anàloga i partint de la mateixa solució teòrica, es projecta una segona implementació, anomenada SOSFul, que proposa una actualització de l'estàndard SOS de manera que siga més lleuger, eficient i fàcil d'emprar. El SOSFul té una projecció més ambiciosa quan aborda la Internet de les Coses, un CPS més complex que les xarxes de sensors. Com en el cas del SOSLite, es realitzen proves i es valida mitjançant un cas d'ús. Així, tant el SOSLite com el SOSFul, es projecten com a solucions d'interoperabilitat en els CPS. Ambdues implementacions parteixen de la proposta teòrica de SOS lleuger, i es troben disponibles de forma gratuïta i en codi lliure per a ser emprades per la comunitat investigadora a fi de continuar el seu desenvolupament i augmentar-ne l'ús. / Pradilla Ceron, JV. (2016). SOSLite: Soporte para Sistemas Ciber-Físicos y Computación en la Nube [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/76808 / TESIS
86

Lean and Industry 4.0 - Synergies and Challenges

Rhawi, Sebastian January 2021 (has links)
The purpose of this study is to investigate the relationship of two significant concepts withinthe manufacturing industry. Namely, the widely popular Lean production and the arising Industry 4.0. The lack of a common framework concerning their relationship requires further exploration, as stated by several researchers. For companies to stay competitive within a changing market it is of importance to adapt to new technologies, indicating that the understanding of this relationship is essential, as Lean production is extensively used in industries today. To increase the understanding of the concepts and their relationship three research questions were formulated, as followed: RQ 1: How can Industry 4.0 support Lean production? RQ 2: How can Lean production support the implementation of industry 4.0? RQ 3: What are the challenges of implementing Industry 4.0 in Lean production? The study was conducted using qualitative research methods such as the narrative literature review and thematic analysis, allowing for the identification of themes and structuring of the study in a narrative approach. Second-hand data was collected through academic databases using search terms highly relevant to the research questions. The theoretical framework of the study provides a foundation for the understanding of the concepts. Whereas the results are centered around the relationship of Industry 4.0 and Lean production with themes relevant to the research questions and subthemes to follow. The analysis highlights important aspects of the results in relation to the theoretical framework, while also discovering insights connecting the research questions together. The conclusion presents aspects of how Industry 4.0 technologies can support Lean production through factors such as increased continuous improvement, support of people, improved JIT, Kanban, maintenance and communications. Where the general benefits will be productivity, quality and speed of introducing new products, adapting to high variability of market demand. Furthermore, describing how Lean production can support the implementation of Industry 4.0, as the degree of Lean maturity directly influences the efficiency of Industry 4.0 implementation. The employment of Lean principles such as continuous improvement, focus on people and standardization can result in a more effective implementation and utilization of Industry 4.0. Challenges of implementing Industry 4.0 in Lean production such as the risk of counterproductive implementation because of the lack of common framework, limitations of certain Lean practices, Lean professionals and ICT professionals limited knowledge of eachother's fields and the understanding of how to apply Industry 4.0 based on lean principles. Lastly, recommendations are offered for companies aspiring to implement Industry 4.0, as they should evaluate their current level of Lean maturity in order to understand when it is most efficient to incorporate the new technologies. Companies seeking to aid their Lean objectives should concentrate on technologies such as IoT and CPS as they seem to have the most positive impact on Lean. In addition, recommending further research regarding the relationship of Industry 4.0 readiness and Lean maturity, exploring which degree of Lean maturity to efficiently integrate and utilize certain Industry 4.0 technologies and when to implement certain Industry 4.0 technologies to aid the advancement of Lean maturity.
87

Interfacing Digital and Physical Twins with a Microservice Architecture

Wintercorn, Oskar January 2022 (has links)
Throughout history, humans have proven to develop and improve their quality of life constantly. Incorporating mechanical principles into otherwise manual labor was one such aspect. Today, introducing mechanization to the industry and steam power is regarded as the first industrial revolution. Since then, a second and a third have followed, introducing concepts such as electricity, automation, computers, and computerization. Finally, in 2011 the fourth industrial revolution was introduced as Industry 4.0 by a project started in Germany, which considers digitalization. Industry 4.0 uses concepts such as Cyber-Physical Systems (CPS), the Internet of Things (IoT), and cloud computing. The goal of these concepts is to be able to further the capabilities of automation in the industry, creating smart factories. A problem experienced today when making changes to the production line is that an immense amount of hard coding is required for the Programmable Logic Controller (PLC) controlling the system as well as for the system controlling the factory. The Eclipse Arrowhead Framework addresses these issues by applying a particular set of parameters to all systems within the IT infrastructure. The Arrowheadframework offers parameters such as orchestrator, authorization, and a service registry to each system incorporated within the framework. By applying this, the System of Systems (SoS) and the parameters provided by the Arrowhead framework create a local cloud. In doing so, each system within a factory belongs to its local cloud, building a factory made of a cluster of local clouds. By applying the ideas of Industry 4.0, a proof of concept is created, showing that today’s industry would benefit from using the concepts stated above with digital twins. The thesis explores and proves that, with the help of digital twins, today’s industry can cut down on manufacturing process development. In addition, it reduces the time it takes to apply changes to the production line by enabling machine learning to facilitate human interaction. A model factory created by fischertechnik is used, together with a PLC, as the physical twin in this master thesis. In addition, using Siemens Computer-Aided Design (CAD) software NX, a digital twin is created; this digital twin will communicate with the physical twin to simulate the behavior of the physical twin in real-time. A server has been created and is acting as a hub of communication for both of the twins. The use of the digital twin to communicate with the physical twin will enable tremendous advances in automation regarding industry 4.0.
88

Hydrobatics: Efficient and Agile Underwater Robots / Hydrobatik: Effektiva och Smidiga Undervattensroboter

Bhat, Sriharsha January 2020 (has links)
The term hydrobatics refers to the agile maneuvering of underwater vehicles. Hydrobatic capabilities in autonomous underwater vehicles (AUVs) can enable increased maneuverability without a sacrifice in efficiency and speed. This means innovative robot designs and new use case scenarios are possible. Benefits and technical challenges related to hydrobatic AUVs are explored in this thesis. The dissertation contributes to new knowledge in simulation, control and field applications, and provides a structured approach to realize hydrobatic capabilities in real world impact areas. Three impact areas are considered - environmental monitoring, ocean production and security. A combination of agility in maneuvering and efficiency in performance is crucial for successful AUV applications. To achieve such performance, two technical challenges must be solved. First, these AUVs have fewer control inputs than degrees of freedom, which leads to the challenge of underactuation. The challenge is described in detail and solution strategies that use optimal control and model predictive control (MPC) are highlighted. Second, the flow around an AUV during hydrobatic maneuvers transitions from laminar to turbulent flow at high angles of attack. This renders flight dynamics modelling difficult. A full 0-360 degree envelope flight dynamics model is therefore derived, which combines a multi-fidelity hydrodynamic database with a generalized component-buildup approach. Such a model enables real-time (or near real-time) simulations of hydrobatic maneuvers including loops, helices and tight turns. Next, a cyber-physical system (CPS) is presented -- it safely transforms capabilities derived in simulation to real-world use cases in the impact areas described. The simulator environment is closely integrated with the robotic system, enabling pre-validation of controllers and software before hardware deployment. The small and hydrobatic SAM AUV (developed in-house at KTH as part of the Swedish Maritime Robotics Center) is used as a test platform. The CPS concept is validated by using the SAM AUV for the search and detection of a submerged target in field operating conditions. Current research focuses on further exploring underactuated control and motion planning. This includes development of real-time nonlinear MPC implementations running on AUV hardware, as well as intelligent control through feedback motion planning, system identification and reinforcement learning. Such strategies can enable real-time robust and adaptive control of underactuated systems. These ideas will be applied to demonstrate new capabilities in the three impact areas. / Termen hydrobatik avser förmåga att utföra avancerade manövrer med undervattensfarkoster. Syftet är att, med bibehållen fart och räckvidd, utvigda den operationella förmågan i manövrering, vilket möjliggör helt nya användningsområden för maximering av kostnadseffektivitet. I denna avhandling undersöks fördelar och tekniska utmaningar relaterade till hydrobatik som tillämpas på undervattensrobotar, vanligen kallade autonoma undervattensfarkoster (AUV). Avhandlingen bidrar till ny kunskap i simulering, reglering samt tillämpning i experiment av dessa robotar genom en strukturerad metod för att realisera hydrobatisk förmåga i realistiska scenarier.  Tre nyttoområden beaktas - miljöövervakning, havsproduktion och säkerhet. Inom dessa nyttoområden har ett antal scenarios identifierats där en kombination av smidighet i manövrerbarhet samt effektivitet i prestanda är avgörande för robotens förmåga att utföra sin uppgift. För att åstadkomma detta måste två viktiga tekniska utmaningar lösas. För det första har dessa AUVer färre styrytor/trustrar än frihetsgrader, vilket leder till utmaningen med underaktuering. Utmaningen beskrivs i detalj och lösningsstrategier som använder optimal kontroll och modellprediktiv kontroll belyses. För det andra är flödet runt en AUV som genomför hydrobatiska manövrar komplext med övergång från laminär till stark turbulent flöde vid höga anfallsvinklar. Detta gör flygdynamikmodellering svår. En full 0-360 graders flygdynamikmodell härleds därför, vilken kombinerar en multi-tillförlitlighets hydrodynamisk databas med en generaliserad strategi för komponentvis-superpositionering av laster. Detta möjliggör prediktering av hydrobatiska manövrar som t.ex. utförande av looping, roll, spiraler och väldigt snäva svängradier i realtids- eller nära realtids-simuleringar. I nästa steg presenteras ett cyber-fysikaliskt system (CPS) – där funktionalitet som härrör från simuleringar kan överföras till de verkliga användningsområdena på ett effektivt och säkert sätt. Simulatormiljön är nära integrerad i robot-miljön, vilket möjliggör förvalidering av reglerstrategier och mjukvara innan hårdvaruimplementering. En egenutvecklad hydrobatisk AUV (SAM) används som testplattform. CPS-konceptet valideras med hjälp av SAM i ett realistiskt sceanrio genom att utföra ett sökuppdrag av ett nedsänkt föremål under fältförhållanden. Resultaten av arbetet i denna licentiatavhandling kommer att användas i den fortsatta forskningen som fokuserar på att ytterligare undersöka och utveckla ny metodik för reglering av underaktuerade AUVer. Detta inkluderar utveckling av realtidskapabla ickelinjära MPC-implementeringar som körs ombord, samt AI-baserade reglerstrategier genom ruttplaneringsåterkoppling, autonom systemidentifiering och förstärkningsinlärning. Sådan utveckling kommer att tillämpas för att visa nya möjligheter inom de tre nyttoområdena. / SMaRC
89

Digital mapping of critical infrastructure : Design of a component data collection method for small-scale power grids

Rapp, Axel January 2023 (has links)
Critical infrastructures (CIs) distributing water, oil, gas, electricity, etc., to community residents and businesses, leverage cyber-physical systems (CPSs) to supervise and control the physical processes that these services entail. Over recent decades, these systems have moved to implement more modern IT-resembling solutions using Supervisory Control and Data Acquisition Systems (SCADA) for increased reliability, scalability, and remote connectivity. This change exposes these highly critical systems to new threats and vulnerabilities. One approach to mitigate the risks faced by these systems is to perform analysis on digital representations in the form of digital models or digital shadows of the CPSs. However, this is not a trivial task in practice. These practical issues are explored in this design science research through the development of a guidance process to perform the data collection necessary to create a static digital model of a small-scale power grid CPS in Sweden. The results show that it is possible to gather information on the CPS components through the four approaches: SCADA system exports, documentation information, CLI scripting, and network scanning. While the artefact presented in this report demonstrates these results, challenges still remain such as a lack of SCADA export tools, reaching the SCADA network with scanning tools in a responsible manner, and accessing insights into the complete documentation held by the organisations. The researcher suggests these topics for future research directions.
90

PROACTIVE VULNERABILITY IDENTIFICATION AND DEFENSE CONSTRUCTION -- THE CASE FOR CAN

Khaled Serag Alsharif (8384187) 25 July 2023 (has links)
<p>The progressive integration of microcontrollers into various domains has transformed traditional mechanical systems into modern cyber-physical systems. However, the beginning of this transformation predated the era of hyper-interconnectedness that characterizes our contemporary world. As such, the principles and visions guiding the design choices of this transformation had not accounted for many of today's security challenges. Many designers had envisioned their systems to operate in an air-gapped-like fashion where few security threats loom. However, with the hyper-connectivity of today's world, many CPS find themselves in uncharted territory for which they are unprepared.</p> <p><br></p> <p>An example of this evolution is the Controller Area Network (CAN). CAN emerged during the transformation of many mechanical systems into cyber-physical systems as a pivotal communication standard, reducing vehicle wiring and enabling efficient data exchange. CAN's features, including noise resistance, decentralization, error handling, and fault confinement mechanisms, made it a widely adopted communication medium not only in transportation but also in diverse applications such as factories, elevators, medical equipment, avionic systems, and naval applications.</p> <p><br></p> <p>The increasing connectivity of modern vehicles through CD players, USB sticks, Bluetooth, and WiFi access has exposed CAN systems to unprecedented security challenges and highlighted the need to bolster their security posture. This dissertation addresses the urgent need to enhance the security of modern cyber-physical systems in the face of emerging threats by proposing a proactive vulnerability identification and defense construction approach and applying it to CAN as a lucid case study. By adopting this proactive approach, vulnerabilities can be systematically identified, and robust defense mechanisms can be constructed to safeguard the resilience of CAN systems.</p> <p><br></p> <p>We focus on developing vulnerability scanning techniques and innovative defense system designs tailored for CAN systems. By systematically identifying vulnerabilities before they are discovered and exploited by external actors, we minimize the risks associated with cyber-attacks, ensuring the longevity and reliability of CAN systems. Furthermore, the defense mechanisms proposed in this research overcome the limitations of existing solutions, providing holistic protection against CAN threats while considering its performance requirements and operational conditions.</p> <p><br></p> <p>It is important to emphasize that while this dissertation focuses on CAN, the techniques and rationale used here could be replicated to secure other cyber-physical systems. Specifically, due to CAN's presence in many cyber-physical systems, it shares many performance and security challenges with those systems, which makes most of the techniques and approaches used here easily transferrable to them. By accentuating the importance of proactive security, this research endeavors to establish a foundational approach to cyber-physical systems security and resiliency. It recognizes the evolving nature of cyber-physical systems and the specific security challenges facing each system in today's hyper-connected world and hence focuses on a single case study. </p>

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