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This paper presents the wrench capability analysis, the controller design, and experimental results of an aerial robot flying gripper. This robot uses four quadrotors to actuate four fingers such as to grasp and manipulate large size objects. The yaw motion of each quadrotor is used to open/close one of the four fingers. A method is proposed to analyze its manipulability considering inequality constraints such as the propellers’ capabilities and equality constraints such as the yaw torque applied by each quadrotor to open or close a finger and the equilibrium conditions of passive joints. This allows concluding on the full manipulability of the robot and evaluating its force and torque capabilities. A dynamic control allocation algorithm is implemented to distribute the control effort among all quadrotors while guaranteeing an achievable solution satisfying the aforementioned constraints. A proof of concept is realized and allows presenting preliminary experimental results of the flying gripper.

This thesis proposes a new concept of aerial manipulation robot named Flying Gripper that is intended to perform grasping, manipulating, and transporting of large objects autonomously. The Flying Gripper robot is composed of four quadrotors, four self-adaptive fingers and a body structure. The main contributions of these works are: (1) an original mechanical concept using multiple quadrotors to obtain full manipulability in SE(3) and taking advantage of their yaw rotations to actuate a self-adaptive and intrinsically safe grasping mechanism; (2) a wrench capability analysis method taking into account the equality and inequality constraints imposed by actuation limits, mechanical stops and equilibrium relations; (3) a model predictive controller to deal with unknown mass, inertia and center of mass due to the grasped object; (4) a Dynamic Control Allocation algorithm to distribute the control output in a way that guarantees the continuity of actuator's velocity, improves the energy efficiency and satisfies the robot mechanical limits.Numerical simulations and experimental tests have been carried out to validate the controller performances.; Cette thèse propose un nouveau concept de robot de manipulation aérienne appelé Flying Gripper. Ce robot est un manipulateur aérien, destiné à la saisie, la manipulation et le transport de grands objets de manière autonome. Le robot Flying Gripper est composé de quatre quadrotors, de quatre doigts auto-adaptatifs et d'un châssis. Les principaux apports de ces travaux sont: (1) un concept mécanique original reposant sur l'utilisation de plusieurs quadrotors et tirant parti de la rotation en lacet des quadrotors pour actionner un mécanisme de préhension auto-adaptatif et intrinsèquement sûr (2) une méthode pour analyser des torseurs disponibles en tenant compte des contraintes d'égalité et d'inégalité imposées par les limites d'actionnement, les butées mécaniques et les relations d'équilibre; (3) une commande prédictive permettant de manipuler l'objet saisie avec une masse, des inerties et un centre de masse inconnus; (4) un algorithme d'allocation de contrôle dynamique pour la distribution de l'effort de contrôle, de manière à optimiser l'efficacité énergétique et à assurer la continuité de la commande, en considérant les limites mécaniques du robot.Des simulations numériques et des tests expérimentaux ont été effectués pour valider les performances du contrôleur.

In the big data era, the digital revolution has driven the entire financial industry to collect, store and analyze massive volumes of data nowadays than it ever has in history. With the overwhelming scale of data, new technologies are needed to derive competitive advantage and unlock the power of the data, including the approaches people use for financial risk management. In this dissertation, we study how advanced data mining techniques can play essential roles in financial risk management. Specifically, we provide case studies to apply data mining techniques in three application scenarios for financial risk management. The first study exploits a special type of fraudulent trading ring pattern in the financial market, and defines the so-called blackhole and volcano patterns to identify the fraud. A blackhole mining framework consisting of two pruning schemes is developed. The first pruning scheme is to exploit the concept of combination dominance to reduce the exponential growth search space. The second pruning scheme is an approximate approach, which can strike a balance between the efficiency and the completeness of blackhole mining. The second study exploits the problem of contract risk management. In particular, how IT service providers can leverage the experiences and lessons learnt from historical contracts to prevent similar issues from reoccurring in the future, in order to mitigate the project risks, ensure smooth delivery and continuous profitability. Along this line, we investigate how to predict potential risks for new contracts based on their similarities with existing ones, and develop a new approach as an extension of the Mahalanobis distance metric learning framework to solve the problem. The third study examines the application of cluster analysis in bankruptcy pattern learning and financial statement fraud detection. By leveraging the domain knowledge in accounting area, valuable features from financial statement can be extracted. Clustering technique is then applied to identify the clustering effect of bankrupt companies in different business sectors. Finally, the most indicative financial features for the bankrupt companies in the business sector can be uncovered from the hidden data and validated by significant tests.

We classify the compact 3-manifolds whose boundary is a union of 2-spheres, and which embed in T ×I ×I, where T is a triod and I the unit interval. This class is described explicitly as the set of punctured handlebodies. We also show that any 3-manifold in T × I × I embeds in a punctured handlebody.

The main objective of this thesis is to study Heegaard diagrams and their applications. First, we investigate Heegaard diagrams of closed 3-manifolds and introduce the circle and chord presentation for a connected, closed 3-manifold. The equivalence problem for Heegaard diagrams after connected sum moves and Dehn twists will be investigated. Presentations will be used to detect reducible Heegaard diagrams and homeomorphic 3-manifolds. We also investigate Heegaard diagrams of the 3-sphere. The main result of this part is that if two Heegaard diagrams of the 3-sphere have the same genus, then there is a sequence of connected sum moves and Dehn twists to pass from one to the other. If we use connected sum moves only, Heegaard curves can be changed to primitive curves and if we use Dehn twists only Heegaard curves can be brought into a simple position. Finally, we construct an immersion of a compact, orientable, connected 3-manifold with non-empty boundary into R³ with at most double and triple points as singularities. Further, we prove that if the boundary of the 3-manifold consists of 2-spheres and the 3-manifold can immerse into R³ with only double points as singularities, then the 3- manifold must be a punctured 3-sphere or a punctured (S¹ x S²)# • • • #(S¹ x S²).