Kalinka R.l.j.c. Branco
University of Sao Paulo, Computer System, Faculty Member
In real-time systems, when failures of any nature come to happen, high-value assets are put at risk and in some cases even human lives. Due to this high criticality, developing improvements to these systems in order to increase their... more
In real-time systems, when failures of any nature come to happen, high-value assets are put at risk and in some cases even human lives. Due to this high criticality, developing improvements to these systems in order to increase their safety becomes a topic of high importance. This research reviews handoff procedures in IPv6 networks to help identify those with lower latency and low packet loss during the operation, aiming to increase the efficiency of general communication in these systems. For this, some handoff techniques found in the literature are simulated and, from the obtained results, performance comparisons are presented following specific statistical techniques to evaluate the performance of computational systems. Finally, a discussion on the application of these techniques in critical embedded systems is presented, specially unmanned vehicles.
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Due to their characteristics, Unmanned Aerial Vehicles (UAVs) are natural candidates to be integrated to the Internet of Things (IoT). However, offering UAV services through the IoT and Cloud Computing is not an easy task. Resources and... more
Due to their characteristics, Unmanned Aerial Vehicles (UAVs) are natural candidates to be integrated to the Internet of Things (IoT). However, offering UAV services through the IoT and Cloud Computing is not an easy task. Resources and services made available to clients need to be properly identified and registered; the UAV must be prepared to provide services autonomously to both human and machine clients, which can be very heterogeneous regarding to computational and networking resources; information security and data privacy must be taken into account. In this paper, we present the Service Exchange Management Unit (SEMU), a service provision platform for UAVs that aims to support service exchange taking into account portability and security issues. The platform design and operation are outlined, exposing how SEMU can support UAVs and other types of vehicles to provide services to each other and to external clients, making it possible for them to be integrated in the IoT.
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Unmanned Aerial Vehicles (UAVs) have gained popularity and are current applied in many fields. They have benefited from the recent technology development and have now increased connectivity, which allows them to achieve higher levels of... more
Unmanned Aerial Vehicles (UAVs) have gained popularity and are current applied in many fields. They have benefited from the recent technology development and have now increased connectivity, which allows them to achieve higher levels of mission complexity and coverage. Among others, security is considered one of the greatest challenges for UAV usage acceptance from the general public, and it scales when this vehicle can communicate with other vehicles and/or systems. This paper presents Cloud-SPHERE, a security approach for unmanned vehicles to communicate and provide services securely, targeting their integration into the IoT ecosystem. The design and operation is outlined and preliminary prototyping results are presented.
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In this paper we propose an evaluation and comparison of guidelines and techniques that allow not only the creation of secure Web services, but also the validation of the services used to determine whether the application has the desired... more
In this paper we propose an evaluation and comparison of guidelines and techniques that allow not only the creation of secure Web services, but also the validation of the services used to determine whether the application has the desired characteristics related to performance and security. In this sense it is crucial evaluating the cryptographic algorithms and key length used. The results obtained allow to determine, based on specified objectives, the impact of security mechanisms used in application performance.
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Popularly known as drones, unmanned aerial vehicles (UAVs) have been applied in several fields, usually operating in cooperative and collaborative swarms to enable the execution of more dynamic missions. Thus, the new Flying Ad Hoc... more
Popularly known as drones, unmanned aerial vehicles (UAVs) have been applied in several fields, usually operating in cooperative and collaborative swarms to enable the execution of more dynamic missions. Thus, the new Flying Ad Hoc Networks (FANETs) paradigm has emerged, a subset of mobile ad hoc networks with specific characteristics that arise from the aviation context. Recently, the ideas from FANETs have started to be synthesized with those from the Internet of Things (IoT), originating the Internet of Flying Things (IoFT), a paradigm which enables an important new level of applications, solves known issues in UAVs and IoT, and expands the range of future applications. This chapter introduces the Internet of Flying Things, describing both the potential new degree of freedom provided to current and future applications and the new challenges for security and safety, before ending with an overview of open issues and new trends for future networks.
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Embedded systems are associations between hardware and software designed to perform a specific function. These systems are usually part of a larger system and their wireless communications are a hallmark. Therefore, it is important to... more
Embedded systems are associations between hardware and software designed to perform a specific function. These systems are usually part of a larger system and their wireless communications are a hallmark. Therefore, it is important to guarantee a secure communication by ensuring the confidentiality of information, which is obtained through cryptography. Security has not traditionally been considered a requirement in embedded systems design and the application of specific security techniques to these devices is still incipient. This paper presents a performance evaluation analysis of cryptographic algorithms in embedded systems (namely RC2, AES, Blowfish, DES, 3DES, ECC and RSA). Parameters considered in the analysis are average processor and memory usage, response time and power consumption. The results show that symmetric and asymmetric algorithms such as Blowfish and ECC have a good performance in embedded systems when properly chosen for each situation.
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The Extended Kalman Filter (EKF) and Unscented Kalman Filter (UKF) are methods usually applied in the sensor fusion for Unmanned Aerial Vehicles due to its nonlinear navigation equations. This paper presents a comparison between the two... more
The Extended Kalman Filter (EKF) and Unscented Kalman Filter (UKF) are methods usually applied in the sensor fusion for Unmanned Aerial Vehicles due to its nonlinear navigation equations. This paper presents a comparison between the two filters considering the position, velocity and attitude of the vehicle and the IMU bias. The simulation experiments are designed according to performance evaluation techniques for two trajectories and different state vectors. The results show that the EKF has a lower computational cost than UKF, but the latter provides smaller errors for most of the states. It also show that the bias estimation influences positively the solution granted by the EKF.
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For intelligent vehicles to become a reality, further research and development must be performed, addressing the needs of multidisciplinary approaches like integrated control systems, communication and network, security algorithms,... more
For intelligent vehicles to become a reality, further research and development must be performed, addressing the needs of multidisciplinary approaches like integrated control systems, communication and network, security algorithms, artificial intelligence, verification and validation, neural networks, safety assets and other technological concerns. The goal of this workshop is to explore the challenges and innovative solutions regarding intelligent vehicles, considering the implications of security and real-time issues on safety and certification, which emerge when introducing networked, autonomous and cooperative functionalities. It aims at joining together in an active debate, researchers and practitioners from several communities, namely dependability and security, realtime and embedded systems, intelligent transportation and mobile robot systems. This workshop is aimed at exploring the challenges and innovative solutions related to the security and safety of intelligent vehicles.
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The use of unmanned aerial vehicles (UAV s) has been growing not only in military applications, but also in civilian. UAVs have enormous potential for use, which mostly still are unexplored. For the use of UAV s in the airspace, not only... more
The use of unmanned aerial vehicles (UAV s) has been growing not only in military applications, but also in civilian. UAVs have enormous potential for use, which mostly still are unexplored. For the use of UAV s in the airspace, not only Brazilian new studies on methods of analysis and technologies should be incorporated into navigation systems, control among others, promoting security mechanisms for these aircraft. Implement security mechanisms using a platform with operating systems and botnet to simulate such attack Distributed Denial of Service (DDoS) in UAVs is an important task when it is aimed at containment and mitigation of attacks on this type of platform.
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International audienc
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Resumo. Este artigo tem como objetivo demonstrar a viabilidade da melhoria no tempo de execução de algoritmos utilizados para o processamento de imagens médicas por meio do uso da computação paralela distribuída. Técnicas de processamento... more
Resumo. Este artigo tem como objetivo demonstrar a viabilidade da melhoria no tempo de execução de algoritmos utilizados para o processamento de imagens médicas por meio do uso da computação paralela distribuída. Técnicas de processamento de imagens foram ...
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Abstract, This paper addresses the problem of constructing suitable metrics for the evaluation of computer system heterogeneity. There are seveml metrics available in the open litemture that evaluates the heterogeneity degree of a given... more
Abstract, This paper addresses the problem of constructing suitable metrics for the evaluation of computer system heterogeneity. There are seveml metrics available in the open litemture that evaluates the heterogeneity degree of a given system. However, this ...
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Formation flying control consists of the design of distributed control systems able to govern the relative distances between multiple vehicles flying in formation, avoiding collisions, and meeting the required performance and stability... more
Formation flying control consists of the design of distributed control systems able to govern the relative distances between multiple vehicles flying in formation, avoiding collisions, and meeting the required performance and stability specifications. In this paper, we are proposing a cooperative formation flying control with collision avoidance. The Unmanned Aerial Vehicles (UAVs) cooperative control is performed by a decentralized leader follower formation using techniques from algebraic graph theory. The collision avoidance is based on the recently developed algorithm named ORCA (Optimal Reciprocal Collision Avoidance). ORCA is an algorithm that under ideal conditions of mutual cooperation ensures a free collision scenario with minor variation of trajectory and adjustment of speed. This algorithm has demonstrated robustness for generic situations to collision avoidance. Its great advantage is instead of acting in an isolated state of pure repulsion works by applying a minimum correction in the idealized vehicle speed so that it goes through a secure path without collisions. The integration of these two strategies is given and is very useful. Initially was calculated the convergence speed in formation based in a relative position. Using ORCA and global state was chosen the closest safe speed and finally was calculated the final speed. Virtual obstacles were inserted in the model to show the model behaviour and reliability allowing the UAV hit the target avoiding obstacles. Simulation results of UAVs in formation flying to a determined target with virtual obstacles show the effectiveness of the proposed approach.
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Unmanned aerial vehicles (UAVs) are a type of safety-critical system, which demand the verification of dependability properties in different levels of abstraction in order to achieve certification and to be released for operation.... more
Unmanned aerial vehicles (UAVs) are a type of safety-critical system, which demand the verification of dependability properties in different levels of abstraction in order to achieve certification and to be released for operation. Existing model-based techniques have been successfully used in the industry, and recommended by safety standards in automotive and aerospace domains to support system design and dependability analysis. However, there is a lack of a context-aware and systematic approach to support the usage of model-based techniques to support dependability analysis in the UAV domain. This paper presents a systematic and context-aware model-based approach to support dependability analysis and automated generation of artefacts required for safety-certification of UAVs. The approach was applied in SLUGs UAV with the support of HiP-HOPS dependability analysis technique/tool. As a result, the application of the proposed approach enabled the automated generation of dependability artefacts, reducing the effort/costs, and number of errors in performing dependability analysis.
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Different from traditional transport systems, such as cars or trains, which are limited by land transit space, flying cars (such as UAS, drones, and air taxis) do not occupy space with traffic. They have a degree of freedom in space and... more
Different from traditional transport systems, such as cars or trains, which are limited by land transit space, flying cars (such as UAS, drones, and air taxis) do not occupy space with traffic. They have a degree of freedom in space and time, smaller displacement, and consequently, less stress for their users. Large companies and researchers around the world are working with different architectures, algorithms, and techniques to test air taxi transport to serve a significant proportion of people safely and autonomously. One of the main issues surrounding the diffusion of air taxis is safety and security, since a simple failure can lead to the loss of high-value assets, loss of the vehicle, and/or injuries to human lives, including fatalities. In this sense, despite significant efforts, the literature is still specific and limited regarding air taxi safety and security. Therefore, this study aimed to carry out an extensive systematic literature review of the main modern advances in t...
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The goal of this work is to present a systematic literature mapping (SLM) identifying algorithms for the search for data, determining the best path and types of communication between the local server and the drone, as well as possible... more
The goal of this work is to present a systematic literature mapping (SLM) identifying algorithms for the search for data, determining the best path and types of communication between the local server and the drone, as well as possible simulators to validate proposed solutions. The concept, here considered as IoT Off-Grid, is characterized by being an environment without commercial electrical infrastructure and without communication connected to the internet. IoT equipment generates data to be stored on a local server. It collects these data through a drone that searches each local server for later integration with the commercial internet environment. As a result, we have algorithms to determine the best path based on the TSP—travelling salesman problem. Different types of communication between the drone and the server contain the data, predominantly WiFi 802.11. As a simulator, OMNeT++ stands out.
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Research Interests: Psychology and Humanities
2nd International Workshop on Safety and Security of Intelligent Vehicles description.
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Web services are key components in the implementation of Service Oriented Architectures (SOA), which must satisfy proper security requirements in order to be able to support critical business processes. Research works show that a large... more
Web services are key components in the implementation of Service Oriented Architectures (SOA), which must satisfy proper security requirements in order to be able to support critical business processes. Research works show that a large number of web services are deployed with significant security flaws, ranging from code vulnerabilities to the incorrect use of security standards and protocols. This chapter discusses state of the art techniques and tools for the deployment of secure web services, including standards and protocols for the deployment of secure services, and security assessment approaches. The chapter also discusses how relevant security aspects can be correlated into practical engineering approaches.
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Abstract Service-Oriented Architecture (SOA) are having a widespread use in enterprise computing applications, being Web services the most common implementation. The use of SOA has also been proposed for embedded systems, although very... more
Abstract Service-Oriented Architecture (SOA) are having a widespread use in enterprise computing applications, being Web services the most common implementation. The use of SOA has also been proposed for embedded systems, although very little could be found in ...
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The proposed mobile agent collects the load index and performs the distributed scheduling considering the behavior of the different kinds of applications. The environments obtained were considered due to the application of parallel... more
The proposed mobile agent collects the load index and performs the distributed scheduling considering the behavior of the different kinds of applications. The environments obtained were considered due to the application of parallel processing of using medical images as well as the comparison of their performance time to measure them. The objective of this paper is to offer alternatives of processes scheduling aiming at maximize the use of the machines.
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Unmanned Aerial Vehicles (UAVs) have been used in numerous applications, like remote sensing, precision agriculture and atmospheric data monitoring. Vertical takeoff and landing (VTOL) is a modality of these aircrafts, which are capable... more
Unmanned Aerial Vehicles (UAVs) have been used in numerous applications, like remote sensing, precision agriculture and atmospheric data monitoring. Vertical takeoff and landing (VTOL) is a modality of these aircrafts, which are capable of taking off and landing vertically, like a helicopter. This paper presents the definition and modeling of a fixed- wing VTOL, named AVALON (Autonomous VerticAL takeOff and laNding), which has the advantages of traditional aircrafts with improved performance and can take off and land in small areas. The principles of small UAVs development were followed to achieve a better design and to increase the range of applications for this VTOL. Therefore, we present the design model of AVALON validated in a flight simulator and the results show its validity as a physical option for an UAV platform.
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Markov Decision Process (MDP) becomes a standard model for sequential decision making under uncertainty. This planning gives the appropriate sequence of actions to perform the goal of the mission in an efficient way. Often a single agent... more
Markov Decision Process (MDP) becomes a standard model for sequential decision making under uncertainty. This planning gives the appropriate sequence of actions to perform the goal of the mission in an efficient way. Often a single agent makes decisions and performs a single action. However, in several fields such as robotics several actions can be executed simultaneously. Moreover, with the increase of the complexity of missions, the decomposition of an MDP into several sub-MDPs becomes necessary. The decomposition involves parallel decisions between different agents, but the execution of concurrent actions can lead to conflicts. In addition, problems due to the system and to sensor failures may appear during the mission; these can lead to negative consequences (e.g. crash of a UAV caused by the drop in battery charge). In this article, we present a new method to prevent behavior conflicts that can appear within distributed decision-making and to emphasize the action selection if needed to ensure the safety and the various requirements of the system. This method takes into consideration the different constraints due to antagonist actions and wile additionally considering some thresholds on transition functions to promote specific actions that guarantee the safety of the system. Then it automatically computes the rewards of the different MDPs related to the mission in order to establish a safe planning. We validate this method on a case study of UAV mission such as a tracking mission. From the list of the constraints identified for the mission, the rewards of the MDPs are recomputed in order to avoid all potential conflicts and violation of constraints related to the safety of the system, thereby ensuring a safe specification of the mission.
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21st century has seen a lot of progress, especially in robotics. Today, the evolution of electronics and computing capacities allows to develop more precise, faster and autonomous robots. They are able to automatically perform certain... more
21st century has seen a lot of progress, especially in robotics. Today, the evolution of electronics and computing capacities allows to develop more precise, faster and autonomous robots. They are able to automatically perform certain delicate or dangerous tasks. Robots should move, perceive their environment and make decisions by taking into account the goal(s) of a mission under uncertainty. One of the most current probabilistic model for description of missions and for planning under uncertainty is Markov Decision Process (MDP). In addition, there are three fundamental classes of methods for solving these MDPs: dynamic programming, Monte Carlo methods, and temporal difference learning. Each class of methods has its strengths and weaknesses. In this paper, we present our comparison on three methods for solving MDPs, Value Iteration and Policy Iteration (Dynamic Programming methods) and Q-Learning (Temporal-Difference method). We give new criteria to adapt the decision-making method to the application problem, with the parameters explanations. Policy Iteration is the most effective method for complex (and irregular) scenarios, and the modified Q-Learning for simple (and regular) scenarios. So, the regularity aspect of the decision-making has to be taken into account to choose the most appropriate resolution method in terms of execution time. Numerical simulation shows the conclusion results over simple and regular case of the grid, over the irregular case of the grid example and finally over the mission planning of an Unmanned Aerial Vehicle (UAV), representing is a very irregular case. We demonstrate that the Dynamic Programming (DP) methods are more efficient methods than the Temporal-Difference (TD) method while facing an irregular set of actions.
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Unmanned Vehicles can benefit from contextual information to improve their operation and security. In fact, a node in any network might assume different levels of criticality depending on several factors, such as their inner components’... more
Unmanned Vehicles can benefit from contextual information to improve their operation and security. In fact, a node in any network might assume different levels of criticality depending on several factors, such as their inner components’ states, data relevance, provided services, and contextual infor-mation. Being aware of a criticality level for an individual node helps determining more consistent approaches to communication and security/safety implementations. In this paper, the integration of security contextual information in a UV communication architecture is demonstrated, in order to increase its safety, overall security and survivability.
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Unmanned Aerial Vehicle (UAV) is a growing research topic due to its wide range of applications. One of its major challenges is the development of the autopilot, responsible for keeping the aircraft in desired flight conditions and for... more
Unmanned Aerial Vehicle (UAV) is a growing research topic due to its wide range of applications. One of its major challenges is the development of the autopilot, responsible for keeping the aircraft in desired flight conditions and for executing navigation tasks. A navigation task that is usually necessary is the path-following, which guarantees that the aircraft follows a predefined trajectory. It is possible to find several approaches for this function, based in geometric and control techniques; however, compared only for the 2D scenario. Therefore, this paper objective is to present new extended path-following algorithms for the 3D scenario, based in the well-known path-following algorithms Lookahead, Non-Linear Guidance Law (NLGL), Pure Pursuit and Line-of-Sight (PLOS) and Vector Field. The algorithms parameters are obtained with Genetic Algorithm optimisation and a comparison between all of them is performed in an environment with and without wind. The results from the simulations show that Vector Field has the best performance and PLOS has the worse one due to a high effort demanded.
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Unmanned Aerial Vehicles (UAVs) with different configurations exist to supply requirements for diverse applications. One of them is the tailsitter that gathers complementary advantages from Vertical Takeoff and Landing (VTOL) and... more
Unmanned Aerial Vehicles (UAVs) with different configurations exist to supply requirements for diverse applications. One of them is the tailsitter that gathers complementary advantages from Vertical Takeoff and Landing (VTOL) and fixed-wing UAVs. In this paper, we present a new design of a tailsitter UAV, named AVALON (Autonomous VerticAL takeOff and laNding). This UAV is composed of typical actuators and is independent of auxiliary infrastructure for vertical takeoff and landing. An autopilot for the tracking control problem of the AVALON vehicle is also proposed to maintain the aircraft in predefined conditions during all flight stages. Simulations results based on the AVALON equations of motion showed that the control techniques applied to all flight stages enable its use as an UAV platform successfully.