A hexacopter aircraft is a class of helicopter, more specifically of multirotors. The hexacopter has several characteristics (mechanically simple, vertical takeoff and landing, hovering capacities, agile) that give it several operational advantages over other types of aircraft. But its beneficts come at a cost: the hexacopter has a highly nonlinear dynamics, coupled and underactuated which makes it impossible to operate without a feedback controller action. In this work we present a detailed mathematical model for a Vertical Takeoff and Landing (VTOL) type Unmanned Aerial Vehicle (UAV) known as the hexarotor. The nonlinear dynamic model of the hexarotor is formulated using the Newton-Euler method, the formulated model is detailed including aerodynamic effects and rotor dynamics that are omitted in many literature. Three controls schemes, namely Proportional-Derivative-Integral (PID) controller, backstepping and sliding mode (SMC), have been applied to control the altitude, attitude, heading and position of the hexacopter in space. Simulation based experiments were conducted to evaluate and compare the performance of three developed control techniques in terms of dynamic performance, stability and the effect of possible disturbances. This article focuses on modeling strategy and command of a kind hexarotor type unmanned aerial vehicle (UAV). These developments are part of the overall project initiated by the team (EAS) of the Computer Laboratory, systems and renewable energy (LISER) of the National School of Electrical and Mechanical (ENSEM).
Risk management methodologies, such as Mehari, Ebios, CRAMM and SP 800-30 (NIST) use a common step based on threat, vulnerability and probability witch are typically evaluated intuitively using verbal hazard scales such as low, medium, high. Because of their subjectivity, these categories are extremely difficult to assign to threats, vulnerabilities and probability, or indeed, to interpret with any degree of confidence. The purpose of the paper is to propose a mathematical formulation of risk by using a lower level of granularity of its elements: threat, probability, criteria used to determine an asset's value, exposure, frequency and existing protection measure.
Abstract-Universities in the public and private sectors depend on information technology and information systems to successfully carry out their missions and business functions. Information systems are subject to serious threats that can have adverse effects on organizational operations and assets, and individuals by exploiting both known and unknown vulnerabilities to compromise the confidentiality, integrity, or availability of the information being processes, stored or transmitted by those systems. Threats to information systems can include purposeful attacks, environmental disruptions, and human/machine errors, and can result in harm to the integrity of data. Therefore, it is imperative that all the actors at all levels in a university information system understand their responsibilities and are held accountable for managing information security riskthat is the risk associated with the operation and use of information systems that support the missions and business functions of their university.The purpose of this paper is to propose an information security toolkit namely URMIS (University Risk Management Information System) based on multi agent systems and integrating with existing information security frameworks and standards, to enhance the security of universities information systems.
We present in this presentation the design of an underwater robot with four propellers, without rudders or diving bars, using the resources of drones [1] for its evolution in the aquatic environment, the modeling is done in a perfect environment without forces or hydrodynamic couples.
Abstract-Problem statement: The Data Warehouse is a database dedicated to the storage of all data used in the decision analysis, it meets the customer requirements, to ensure, in time, that a data warehouse complies with the rules of construction and manages the evolutions necessary of the information system (IS).Results: According to the studies carried out, we see that a system based on a data warehouse governed by the best practices of The Information Technology Infrastructure Library (ITIL) and equipped with a multi-agent system will make it possible our direction to ensure governance tending towards the optimization of the exploitation of the data warehouse.
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