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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.
31

Metodologia de avaliação de segurança das comunicações entre controlador e piloto via enlace de dados (CPDLC) aplicada em áreas terminais. / Safety assessment methodology of controller-pilot data link communications (CPDLC) applied in terminal areas.

Gil, Fernando de Oliveira 18 May 2011 (has links)
Com o crescimento do setor aeronáutico faz-se necessário a criação de novas tecnologias para que a capacidade do sistema possa aumentar sem provocar perdas nos níveis de segurança. Para isso foi criado o CNS/ATM, um paradigma que integra tecnologias de comunicação, navegação e vigilância em um sistema de gerenciamento de tráfego aéreo global. No âmbito das comunicações entre controlador e piloto, o atual sistema de fonia via rádio analógico é substituído por um enlace de dados, chamado de Controller-Pilot Data Link Communication (CPDLC). Esta alteração promove polêmica entre aeronautas e autoridades, de forma que é essencial um estudo aprofundado que comprove sua eficácia. Dessa forma, esta pesquisa visa avaliar a segurança do CPDLC quando utilizado em Áreas Terminais do Espaço Aéreo. Para a realização desta pesquisa, foi criada uma metodologia de avaliação de segurança utilizando simuladores de voo, de tráfego aéreo e de comunicação CPDLC combinados com uma análise por meio de modelos de Markov. O procedimento de chegada ao aeroporto de Congonhas, situado na Terminal São Paulo, foi utilizado como referência para aplicação desta metodologia. Os resultados obtidos mostraram que o sistema atual de comunicação, via voz, está no limite do atendimento dos níveis internacionais de segurança para a demanda atual. Contudo, a comunicação por enlace de dados atende, e em alguns casos inclusive melhora, o nível de segurança desta região do espaço aéreo. / With the growth of the aviation industry it is necessary to create new technologies that can increase the system capacity without loss in the safety levels. Because of this the CNS/ATM was created, a paradigm that integrates communication, navigation and surveillance technologies with a global air traffic management. For the communications between controllers and pilots, the current system of voice over analog radio is being replaced by a data link, called the Controller-Pilot Data Link Communication (CPDLC). This replacement raises debates between airmen and authorities, demanding a detailed study that proves its effectiveness. Thus, this research aims to evaluate the CPDLC safety when used in Terminal Airspace Areas. For this research, was created a methodology for security assessment using flight, air traffic, and CPDLC simulators combined with a Markov model analysis. The Congonhas airport arrival procedure, located in São Paulo Terminal, was used as reference for this methodology application. The results showed that the current system of voice communication is on the limit of fulfilling the international safety levels for the current demand. However, the data link communication addresses, and in some cases even improve, the safety level for this airspace region.
32

Security and Privacy of Controller Pilot Data Link Communication

Wernberg, Max January 2018 (has links)
Newly implemented technologies within the aviation lack, according to recent studies, built in security measures to protect them against outside interference. In this thesis we study the security and privacy status of the digital wireless Controller Pilot Data Link Communication (CPDLC) used in air traffic management alongside other systems to increase the safety and traffic capacity of controlled airspaces. The findings show that CPDCL is currently insecure and exposed to attacks. Any solutions to remedy this must adhere to its low levels of performance. Elliptical Curve Cryptography, Protected ACARS and Host Identity Protocol have been identified as valid solutions to the system’s security drawbacks and all three are possible to implement in the present state of CPDLC.
33

Metodologia de avaliação de segurança das comunicações entre controlador e piloto via enlace de dados (CPDLC) aplicada em áreas terminais. / Safety assessment methodology of controller-pilot data link communications (CPDLC) applied in terminal areas.

Fernando de Oliveira Gil 18 May 2011 (has links)
Com o crescimento do setor aeronáutico faz-se necessário a criação de novas tecnologias para que a capacidade do sistema possa aumentar sem provocar perdas nos níveis de segurança. Para isso foi criado o CNS/ATM, um paradigma que integra tecnologias de comunicação, navegação e vigilância em um sistema de gerenciamento de tráfego aéreo global. No âmbito das comunicações entre controlador e piloto, o atual sistema de fonia via rádio analógico é substituído por um enlace de dados, chamado de Controller-Pilot Data Link Communication (CPDLC). Esta alteração promove polêmica entre aeronautas e autoridades, de forma que é essencial um estudo aprofundado que comprove sua eficácia. Dessa forma, esta pesquisa visa avaliar a segurança do CPDLC quando utilizado em Áreas Terminais do Espaço Aéreo. Para a realização desta pesquisa, foi criada uma metodologia de avaliação de segurança utilizando simuladores de voo, de tráfego aéreo e de comunicação CPDLC combinados com uma análise por meio de modelos de Markov. O procedimento de chegada ao aeroporto de Congonhas, situado na Terminal São Paulo, foi utilizado como referência para aplicação desta metodologia. Os resultados obtidos mostraram que o sistema atual de comunicação, via voz, está no limite do atendimento dos níveis internacionais de segurança para a demanda atual. Contudo, a comunicação por enlace de dados atende, e em alguns casos inclusive melhora, o nível de segurança desta região do espaço aéreo. / With the growth of the aviation industry it is necessary to create new technologies that can increase the system capacity without loss in the safety levels. Because of this the CNS/ATM was created, a paradigm that integrates communication, navigation and surveillance technologies with a global air traffic management. For the communications between controllers and pilots, the current system of voice over analog radio is being replaced by a data link, called the Controller-Pilot Data Link Communication (CPDLC). This replacement raises debates between airmen and authorities, demanding a detailed study that proves its effectiveness. Thus, this research aims to evaluate the CPDLC safety when used in Terminal Airspace Areas. For this research, was created a methodology for security assessment using flight, air traffic, and CPDLC simulators combined with a Markov model analysis. The Congonhas airport arrival procedure, located in São Paulo Terminal, was used as reference for this methodology application. The results showed that the current system of voice communication is on the limit of fulfilling the international safety levels for the current demand. However, the data link communication addresses, and in some cases even improve, the safety level for this airspace region.
34

Feasibility study: Implementation of a gigabit Ethernet controller using an FPGA

Fält, Richard January 2003 (has links)
<p>Background: Many systems that Enea Epact AB develops for theirs customers communicates with computers. In order to meet the customers demands on cost effective solutions, Enea Epact wants to know if it is possible to implement a gigabit Ethernet controller in an FPGA. The controller shall be designed with the intent to meet the requirements of IEEE 802.3. </p><p>Aim: Find out if it is feasible to implement a gigabit Ethernet controller using an FPGA. In the meaning of feasible, certain constraints for size, speed and device must be met. </p><p>Method: Get an insight of the standard IEEE 802.3 and make a rough design of a gigabit Ethernet controller in order to identify parts in the standard that might cause problem when implemented in an FPGA. Implement the selected parts and evaluate the results. </p><p>Conclusion: It is possible to implement a gigabit Ethernet controller using an FPGA and the FPGA does not have to be a state-of-the-art device.</p>
35

Improvement And Development Of High-frequency Wireless Token-ring Protocol

Kurtulus, Taner 01 January 2011 (has links) (PDF)
STANAG 5066 Edition 2 is a node-to-node protocol developed by NATO in order to communicate via HF media. IP integration is made to be able to spread the use of STANAG 5066 protocol. However, this integration made the communication much slower which is already slow. In order to get faster the speed and communicate within single-frequency multi-node network, HFTRP, which is a derivative of WTRP, is developed. This protocol is in two parts, first is a message design for management tokens exchanged by communicating nodes, and second is the algorithms used to create, maintain, and repair the ring of nodes in the network. Scope of this thesis is to find out a faster ring setup, growing procedure and to implement. Beside, finding optimum values of tuning parameters for HFTRP is also in the scope of this thesis.
36

Feasibility study: Implementation of a gigabit Ethernet controller using an FPGA

Fält, Richard January 2003 (has links)
Background: Many systems that Enea Epact AB develops for theirs customers communicates with computers. In order to meet the customers demands on cost effective solutions, Enea Epact wants to know if it is possible to implement a gigabit Ethernet controller in an FPGA. The controller shall be designed with the intent to meet the requirements of IEEE 802.3. Aim: Find out if it is feasible to implement a gigabit Ethernet controller using an FPGA. In the meaning of feasible, certain constraints for size, speed and device must be met. Method: Get an insight of the standard IEEE 802.3 and make a rough design of a gigabit Ethernet controller in order to identify parts in the standard that might cause problem when implemented in an FPGA. Implement the selected parts and evaluate the results. Conclusion: It is possible to implement a gigabit Ethernet controller using an FPGA and the FPGA does not have to be a state-of-the-art device.
37

Flying is Dangerous - That is why it is so safe : Miscommunication in aviation

Thörnqvist, Christer January 2020 (has links)
In this essay one has been investigating some of the reasons why aviation incidents take place and also examine what strategies there are to minimize the risks - primarily regarding miscommunication which often seems to be a contributing element or a direct cause in aviation mishaps. The aim of this study is to highlight and raise awareness about this field of study from a communicative point of view.The study has been performed using qualitative interviews with pilots, Air Traffic Controllers and other professionals within the aviation industry. The research has been somewhat hampered by the outbreak of the COVID-19 pandemic but not to an extent that would have corrupted the findings.The key results have indicated that miscommunication still is a problem in the aviation industry, but less so on the local national stage than in a global perspective. Two particular occurrences that have been given extra attention are runway incursions and the use of Controller Pilot Data-Link Communications.One has established that there are technical systems available on the market to improve communication performance and that runway incursion is a problem that grows with the complexity of the airport environment. One has also been made aware of the fact that human factors can only be mitigated so far with technology. The principal question has been: How can Miscommunication in Aviation be reduced? / I denna uppsats har vi tittat på några av de bakomliggande orsakerna till att incidenter fortfarande sker inom trafikflyget samt undersökt vilka strategier som föreligger för att minimera dessa risker - primärt pga felkommunikation vilken ofta tenderar att vara en bakomliggande eller direkt utlösande faktor i flygolyckor. Syftet med denna studie är att uppmärksamma och öka medvetenheten om dessa fenomen från en kommunikativ synvinkel.Studien har genomförts medelst en kvalitativ intervjumetod med piloter, flygledare och andra initierade yrkesgrupper inom flygindustrin. Forskningen har hämmats något pga utbrottet av COVID-19 pandemin men inte i en sådan omfattning att resultatet har förvanskats.De huvudsakliga resultaten har indikerat att felkommunikation fortfarande är ett problem inom flygbranschen, men i en långt mindre omfattning på lokal nationell nivå än i ett globalt perspektiv. Två specifika företeelser som har getts extra uppmärksamhet är rullbaneintrång samt användandet av CPDLC (datalänk).Vi har konstaterat att det finns tekniska system på marknaden för att förbättra prestandan på kommunikationen samt att rullbaneintrång är ett problem som växer med flygplatsens storlek och komplexitetsgrad. Vi har också uppmärksammats på att den mänskliga faktorn endast delvis kan undanröjas med hjälp av teknologi. Den huvudsakliga fågeställningen har varit: Hur kan felkommunikation inom flyget reduceras
38

Integrace civilních bezpilotních prostředků do neřízeného vzdušného prostoru / Integration of unmanned air vehicles to uncontrolled airspace

Kohutek, Jakub January 2011 (has links)
The master’s thesis expresses an opinion on trends in UAV integration into non-segregated airspace issue. In the beginning, barriers to integration are characterized and a broader context is shown. Since necessity of the technical realization of the “see and be seen” principle exists, requirements for so called Sense and Avoid systems are presented. Various methods of Sense and Avoid are briefly described, highlighting their contribution to air safety and their potential for future development. The UAV communication topic is described in the last chapter, providing a list of the volume of transmitted messages, analyzing data link frequencies and selecting appropriate means of UAV operations.
39

Modelování L2 protokolů zajišťujících bezsmyčkovost / Modelling of L2 Loop-Preventing Protocols

Hrnčiřík, Matej January 2012 (has links)
This thesis informs about currently used technologies, which provide loop protection on data link layer of computer networks. It clarifies issues of Ethernet networks. Chosen protocols are then closely described. There are presented advantages and disadvantages of chosen protocols and they are compared to other technologies. Practical section describes the initial implementation of IS-IS in OMNeT++ environment, which serves as the basic building block of TRILL protocol. An important issue is to verify correctness of implementation.
40

Regional airspace design: a structured systems engineering approach

Fulton, Neale Leslie, Aerospace & Mechanical Engineering, Australian Defence Force Academy, UNSW January 2002 (has links)
There has been almost fifteen years of political controversy surrounding changes to the rules and procedures by which aircraft conduct their flight within regional Australia. Decisions based on a predominately heuristic (rule of thumb) approach to design have had many adverse consequences for the integrity of the proximity warning function. A sound mathematical model is required to establish this function on a mature engineering foundation. To achieve this, the proximity warning function has been investigated as a hybrid-system. This approach recognises the dual nature of the design: that aircraft dynamics give rise to continuous mathematical models while the communication protocols controlling proximity require discrete mathematical approaches. The blending of each aspect has yielded a deeper insight into the operational limitations and failure modes of this function. The presentation of the thesis follows a design thread through the function. It begins with a description of existing standards and implementations. Risk models are then developed. The pilot interface is recognised as a primary design constraint. Mathematical models are then developed to describe the topology of flow, proximity dynamics, and the scheduling constraints associated with visual, voice, and data-link communications required by the proximity warning function. These analyses show that many aspects of design can be bounded by analytical formulae that bring new robustness to the design and resolve some of the misconceptions arising from the often inaccurate perceptions of present airspace operations. Failure modes, unaccounted for in existing designs are found to actually aggravate failure in the very situations in which the airspace design should be robust and should act to prevent collisions. In particular, there are divergences of performance between the demands required by the system design and the ability of the pilot to deliver such performances. In some cases, these failures may be traced to policy decisions such as service between Instrument Flight Rule and Visual Flight Rule category aircraft. On the basis of the conclusions of this research, a formal engineering review of the proximity warning function is required to assure the containment of the likelihood of mid-air collision for all future operations.

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